Wednesday, June 27, 2012

Software Principles - Agile or not - 1 of 3

I should have been at Tom Gilb’s annual gathering this week - GilbFest as some people call it. Instead I’m sitting at 36,000 feet somewhere over Newfoundland heading for Chicago. I don’t often get out of Europe but maybe my fame is spreading.



The theme at GilbFest this year was Principles - defined by my dictionary as “a fundamental truth or proposition that serves as the foundation for a system of belief or behavior or for a chain of reasoning.” In fact principles is something that has been on my mind a lot over the last year or so. My “What and Why of Agile” which I gave to BCS London a few months ago featured a few thoughts on principles and I started a blog entry on the subject but never finished it.



Now is the time to finish it. Had I been at GilbFest this is what the audience would have heard about, or rather, this blog entry is the first of three instalments on what I would have said.



Let me say I don’t care whether you call these Agile or not, since we can’t define just what Agile is I’m prepared to accept they may just be principles. That said, I will divide the list into “Software Development Principles” and “Agile Software Development Principles” because I think the first set are universally applicable to software development while the second set require you to at least accept the idea of Agile.



I’ll publish these as separate blog entries, there is a lot here. After that I’ll also return to Kelly’s Law which I penned some years ago - before blogs!



Software Development Principles:



Principle 1: Software Development exhibits Diseconomies of Scale


Many, if not most, of us have been brought up with the idea that if we “do” bigger things get cheaper. Buying 2 litres of milk is cheaper than buying 1 litre. Building 1,000,000 identical cars is cheaper than building 10 different cars 100,000 each.



In software this isn’t true. Bigger teams are more difficult to manage, more expensive and less productive per head than smaller teams. This effect is so pronounced that really large teams might be less productive in total than small teams.



For example: a team of five will, per head, be more productive than a team of 25. Still the team of 25 will achieve more in total than the team of 5. However a team of 50 might be less productive than a team of 25 in total.



And its not just teams. Large software releases are more expensive than lots of small releases. Producing software to satisfy 100 users is more expensive than producing software to satisfy 10, or 1.



The effect appears again and again. Its why Lean folk like to emphasis small batch sizes. Unfortunately post-industrial society has internalised the concept of mass production and economies of scale. You, me, everyone, needs to purge themselves of economies of scale thinking and embrace dis-economies of scale if you are going to be be successful in this world.



By the way, I suspect this applies to other industries, more than we realise, however, I am a software guy, I can talk with authority about software so that I’ll stick to there.



Principle 2: Quality is essential - quality makes all things possible


By quality I’m really thinking bugs, I want to see bug-free software. I definitely do not want to see gold plating, I have no time for reusable code (as I said in an earlier blog).



Philip Crossby said it best: “Quality is Free” - Neils Malotaux puts it more accurately if less dramatically “Quality is cheaper.” The basic message is the same: pay attention to quality, rid yourself of rework and it will work out better. I said more about this in my “How Much Quality can we afford?” presentation.



And when we get to Agile I’m quite clear: if you don’t build in quality I don’t see how you can get iterations to work and I have no hope you will ever truly achieve Agile.



I’ll finish here for now, I’ll continue with the Agile Principles in the next entry.



To finish I should say these principles are a work in progress. That doesn’t mean that I intend to change them when things get tough. Rather I mean a) there may be some more I haven’t get identified, b) there might be some even deeper underlying truth below some of these principles.

Friday, June 22, 2012

Intellectual proprerty

Something else that came up at BCS Edinburgh was a question about protecting intellectual property. To be honest, I can’t actually remember the question but I do remember my answer. So since this is a blog, and I don’t need a question to sound off, let me do so….



Protecting your intellectual property (IP), with a patent, is a good idea if only so someone else doesn’t claim the patent and accuse you of breaking their patent. Offset against this is the time and expense of getting the patent.



I don’t really believe that a software patent can protect your IP from the competition, it can slow down the competition, it can make things expensive for them but then, it also makes things more expensive for you and slows you down.



Certainly if you look at the “patent wars” that Google, Microsoft, Oracle and others are engaged in now its hard to see how any of these companies will really benefit. Sure the lawyers will make some money but will any of it really benefit their customers?



And there in lies the really issue with IP: the customer.



Ultimately customers still have the same needs, the same problems, the same demands. Patents only address part of the solution. If you can find another way of addressing the need the IP is meaningless.



So the solution to all of this is really: Innovation.



Seek to innovate to address the customer needs better.


Base your company on innovation and continual change, rather than patents and attempts to freeze technology at some point.


Stay ahead of those who would copy you by innovating, don’t worry about copy-cats, be onto the next thing.



The fly in the ointment here is patents: if you do do something innovative, and you don’t move to protect yourself - a defensive patent - there is a danger that someone else will. I can’t help but see all of this as a diversion from innovating and addressing customer needs.


Thursday, June 21, 2012

Are the Business Patterns more widely applicable?

As I mentioned in my last entry about Business Patterns for Software Developers, the audience at BCS Edinburgh asked several good questions. One of these questions was:



“It strikes me that many of these patterns are more broadly applicable and could be applied outside the software industry. Why have you limited them?”



This is true, if you look at the pattern Customer Co-Created Product you will see it is illustrated with a picture of a Boeing 777. Or look at Single Product Company you will find a picture of a Model-T Ford. Many of the patterns use examples drawn from outside of software, and many of the patterns are applicable in other industries.



This in fact is a question that has been asked many time during the writing and reviewing of these patterns: “why limit them to software?”



There are really four answers: my knowledge, customer segmentation, brevity and application. Let me explain each one in its own right, although in truth the four as interlocked.



My knowledge: I first earned money from selling software in 1986, over 25 years ago. I know the software industry. I’ve worked in other industries (electricity supply and investment banking to name two) but I was always on the software side so I was still in the software industry. I know about this industry so I write about what I know.



This isn’t to say I don’t know about other industries. As I said, I’ve worked on the edges of other industries; I’ve read about other industries, I’ve spoken to people form those industries and studied them on occasions. Ultimately its all business. Still, by writing about what I know best, the area my knowledge is concentrated, I believe I write better and add more to the debate.



Customer Segmentation: A book is a product like any other, now its published it needs to sell -Yes! Buy Business Patterns today! Even better write me a review :)



I consciously decided to target this book at a specific audience, the audience I know best. This shouldn’t be a surprise, the book contains a pattern called Customer Segmentation which says exactly this.



Brevity: By sticking to one domain, an industry I know well, by addressing specific readers, I can write less. I can assume more about the readers existing knowledge and I can write less. Had I tried to write a pattern like Product Roadmap and cover other industries I’d need to generalise it more, add more words, in the process I’d loose the applicability….



Applicability: By applicability I mean I try and make the patterns applicable to the software industry, I try to write about concrete steps you can take in the industry to build these patterns. I might not always succeed but I’m sure if I’d tried to write in more general terms I would have been even less specific. Ultimately the book would have ended up being any other abstract book on business.



This lesson was brought home to me when I wrote my first business patterns: The Porter Patterns. These patterns are not in the book. If you want to read them you can download The Porter Patterns for free from my website - as you can the earlier versions of all the patterns in the book.



The Porter Patterns are based on the work of Professor Michael Porter. He proposed several generic models are analysing businesses - Cost Leader, Market Niche, etc. etc. In analysing these models I realised: they don’t tell yo what to do. The models describe businesses strategies but they are pretty useless at telling you which one is right for your business today.



You could add in Porter’s Five Forces Model but even when you do this there is no advice on what you could do. Because I believe Patterns should help you decide what to do I deliberately moved away form this approach and have not included these Patterns.



So there you go, I am sure that many, if not all, the 36 patterns in Business Patterns for Software Developers are applicable outside of software but I leave it as an exercise to the reader to make the necessary additions.


Friday, June 08, 2012

Business Patterns for Software Developers

On Wednesday night I was in Edinburgh to speak to the local BCS group - I’m sure you remember the British Computer Society, that no longer exists, this was the Charted Institute for IT which just happens to be known as The BCS (obvious really). Anyway, I digress….



I was there to talk about the software business, or more specifically, patterns of software business…. OK, I admit it, I was there to plug my book Business Patterns for Software Developers - sales are going well, although I can always do with more and a few more reviews on Amazon would be well received.



The presentation itself can be downloaded from my website - Business Patterns for Software Developers - or viewed on Slideshare. There must have been 30 or so people there and the presentation was well received.



After the presentation there were several interesting questions which, time allowing, I’d like to reprise in this blog in the coming weeks. Right now I’ll stick to one question and answer.



One of these questions concerned the book’s title: Business Patterns for Software Developers. Someone said they had expected something more technical and they were a little confused by the title. Well, let me explain….



The choice of title was a little complicated. Partly because over the years the name “Business Patterns” has been used by some to refer to code level patterns. Lets be clear - BSP, as I call it for short, doesn’t contain any code.



(I call it BSP because the earliest drafts were entitled Business Strategy Patterns - have a look at the early patterns on my website. Over time I focused the patterns more and more on the domain I know best, software development.)



The title reflects two things - both of which are in the second half “Software Developers.” Firstly I am using the term “Software Developers” in the broadest sense, I am including anyone, or any organisation that creates software. Indeed, one of the earlier versions had the title as “Business Patterns for Software Creators” but that was felt to be a little vague.



Second, when I was writing the book I tried to imagine the reader. Who was going to read this book? What did they look like? Where did they come from?



The people I imagined were code-face hands on developers. People like the members of the ACCU. People who spent most days building someone else’s system and dreamed of building their own product someday. Some of these folk wake up one day and realise that they now hold a management position and they need to understand the business they are in.



In other words I segmented my market. I had personas for my readers. And yes, I imagined specific individuals reading this book. I won’t name them, I don’t want it to go to their heads, I’ll let them guess.



Actually, one person I will name: my younger self. In many ways the developer I was imaging was the younger me, the me that used to - sometimes still does - dream of creating a best selling software application.


Tuesday, June 05, 2012

Dialogue Sheets - Maro, where are you?

For the last few weeks there has been something wrong with the blogger commenting system. Comments get posted but when I come to moderate them there are missing.



Unfortunately this happened with a really good comment from Maro at Thales in Argentina. Maro also posted as Anonymous so I can’t contact him back - Maro are you there? Please contract me!



Maro’s team had been trying my Dialogue Sheets, I think they may have translated one themselves, although we now have one Dialogue Sheet available as a Spanish translation. He has posted his experiences on a blog, DosIdeas - in Spanish but Google will translate.



He also tells me that his team have developed another facilitator less retrospective technique using index cards. I’m looking forward to hearing more about this.


Monday, May 14, 2012

10 Things to make you Agile adoption successfull

One of the closing slides in my Agile Foundations course includes a quote from Ken Schwaber saying that only 30% of teams who attempt Scrum will be successful. What I find interesting about this quote is that it aligns with many other change management studies. Researchers like Harvard Professor John Kotter regularly say 70% of major change efforts fail.

On his blog Ken Schwaber says he doesn’t remember this and instead suggests only 30% will become “excellent development organizations.”

Either way, the prognosis isn’t optimistic. A few months ago, at the end of the course, someone asked the obvious question, a question so obvious I wonder why nobody has asked it before: “What can we do to ensure that we are in the 30% who make it?”

Given that I had the Managing Director, the Director of Technology and most of the technology team in the room it was an excellent opportunity to set the change agenda. And I fluffed it, despite having written a book on the subject I didn’t have a quick answer to hand. But it set me thinking: “What are the 10 things a team can do to make Agile (any flavour) stick?”

Here then is that list, the team in the room will recognise the first three, it was after that that I had to think.

1) Use a physical board: over the last year I have become convinced that the single biggest difference between teams which successfully adopt Agile working and those who try, fail, or end up stuck is the use of an actual physical board.

I know some teams find this difficult, I know some teams are distributed, I know there is technology out there to do this for you but I stand by my point. If you can make it physical, in a place where many, if not all, can see, then you are more likely to succeed.

2) Start collecting and using statistics and other data: velocity, burn-down, bugs identified, bugs logged, etc. etc. Metrics have a bad name in software development - rightly in most cases. But that only means that have been badly collected, managed and used, it doesn’t mean they aren’t useful. At the very least measure your velocity and create a burn-down chart or cumulative flow diagram of the work to do or arising.

3) Engage a coach/consultant: at the risk of being accused of trying to make work for myself I should say you can adopt Agile all by yourself. You can read the books, you can experiment, you can go on courses. But doing it without help makes the whole process slower and increases the risk that you won’t make it to the 30%.

Personally, I find it difficult to know just how an Agile Coach differs from an Agile Consultant. What ever you call the role you want someone who can:
  • Provide advice on which practices and process to adopt, and how to best adopt them
  • Offer examples of what they have seen work, and not work, elsewhere, and how other team tackle similar issues
  • Observe, examine, query and challenge your thinking on what you are doing
  • Challenge your thinking and point out opportunities and idea that you haven’t seen yet
You may need to work with multiple advisors since few will be able to cover all process, practice, technology, product and strategy bases. On very large team it might be worth having full-time consultants although the model I have had most success with is light-touch coaching in tandem with a pull-change model (below).

I don’t believe such an advisor needs to be full time. I practise, and have written before about, light-touch Agile coaching, in this model I return to companies at intervals, perhaps monthly, perhaps more frequently, sometimes less frequently and continue the discussion.

4) Action over talking: action speaks louder than words, until you start trying to do Agile you can’t foresee all the issues and questions which will arise. The longer you spend talking about doing it, and not actually doing it, the more it anticipation will build up, the more more it will look like jus another management fad.

By all means talk about it, plan a bit but there is no real substitute for just getting stuck in and doing it. In particular do not spend your time agonising over whether to do XP or Scrum, or Lean or FDD, or DSDM or Kanban. They are all pretty much of a muchness and you will end you up crafting your own hybrid anyway.

Likewise, discusses a few weeks ago: don’t waste your time looking for evidence, make your own.

Planning your way to Agile is anathema, just do it - JFDI.

5) Give everyone training and start group wide discussions: teams don’t get to be Agile by management deeming “thou shalt be Agile” - although plenty of managers and team leaders have tried the approach. Reading books works for some people but most books go unread, or the words go in one eye and out the other.

If you want to be Agile then invest in taking the time to explain to people what it is. But don’t stop there, make time for people to talk about what Agile is to them, what they like, don’t like, will do, won’t do. Agile is a team sport and unless the team have a shared understanding they will be playing different games.

6) Enthuse, Pull, don’t Push: Anyone who has worked around companies for a few years will have seen management pushing the latest change initiative: ISO 9000, Sig Sigma, CRM, ERP, etc. etc. Someone dreams up these ideas and then a change machine sets about pushing them out.

Apply a lean principle: Pull, don’t push. Forbid the words “change management.” Enthuse individuals and teams, have them ask for Agile. And when they ask give them the help and support they need. This works at the individual level, at the team level, at the company level.

If you are in management this means you need to engineer a pincer movement: you want enthusiasm for change coming from the bottom up to meet your support coming top down. Introducing Agile top-down alone is, in my opinion, as quite likely to kill it - employees are, rationally, skeptical of top-down management change. We live in a post-modern, post-BRP, post-layoffs, post-recession, post-everything world. Employees aren’t children they’ve heard what happens.

Rather than impose change from the top down managers need to build, kindle people’s curiosity, get people asking questions and for help, create bottom-up change initiative and support it. Do everything build the fire without extinguishing it.

The good news is the Agile marketing machine may already have got there ahead of you. People may already be curious about Agile, or even keen to try it - they may even be doing it when you are not looking. If not then find ways to stir interest. When they come asking for support - for budget for speaker, trainers or coaches - or time to go to conferences, give it, give it generously. Offer more, ask when else they need, and above all else: learn to change your own behaviours to match.

7) Be clear on Why you are going Agile: what ever level you are, engineer, tester, project manager, director, look beyond the Agile hype. What is the problem you want “Agile” to fix for you? Understand why you want change and what you expect from it.

Don’t just “get Agile” because it is this month’s fashion, get “Agile” to achieve something more important.

8) Process and technical, Adopt technical side as well as process side: don’t think you can just change the process and it will all be all right. You need to address the technical side too, you need to improve quality, you need to support the engineers, testers and others who are at the code face doing the work.

I’ve come across big companies who view the technical side as somehow dirty: the attitude seems to be “thats technical” or “ they get their hands dirty” or “we can ship it to [Low cost country of choice this week]”.

Get your hands dirty, talk to engineers, adopt Test Driven Development, refactoring, shun big up front design architecture, learn to live with rough designs and evolving architecture. There are real feedback loops here.

9) Get Product Management/Owner flow to developers clear and clean: it isn’t just about fixing the coding side, the requirements side needs to be addressed to. Specifically there needs to be a clear path from someone who represents requirements - typically called a Product Owner or Product Manager and frequently staffed with a Business Analyst - and the development team. Far more negotiation is going to happen over “what” then “when”. Someone needs to represent - and have authority - over that side of things.

10) Structural changes - Functional groups: Staff your teams to do the work for which they are responsible, end functional groups - i.e. database developers and UI developers in separate teams. This is just the first of more structural changes you will need to make. But if you fail at this you won’t get to play again.

There you go, each of those items could be an entry in its own right, maybe one day they will be. Thats enough to get you started. If there was an eleventh is would be: let go of the past, things change, Agile isn’t purely additive. If you don’t stop doing some of your current things you will never see the full benefit. But 11 can wait, those 10 will get your a long way.

Tuesday, May 08, 2012

Points based contracts? Just Say No.

With the points-mini-series still fresh in the mind now seems a good time to say publicly something which I’ve been saying privately for a long time.

Avoid points based contracts. i.e. don’t outsource work, or undertake work, on the basis of points - be they story points, abstract points, nebulous units of time or any other name you give them.

I have one client at the moment who wants their software supplier to sign a points based contract, I’ve advised against it. Another client is trying to sell points based contracts to their clients, while they are having some success - I think they rushed in before they had enough data to understand the implications.

Why do I say this? Well three reasons

First is Goodhart’s Law: “Any observed statistical regularity will tend to collapse once pressure is placed upon it for control purposes.” Put it another way: any measurement metric will change behaviour once it is used for control.

In this context it means: points are very good at measuring story size and team velocity, they can be accurate at predicting when a piece of work will be done. But, if you use them for other purposes - like regulating a contract and making payments - they will change their behaviour. They won’t be so useful for predicting end dates, or for controlling contracts for that matter.

This is a problem many readers will be familiar with from traditional time estimation. Estimates are nominally sought to determine how long a piece or work will take, and thus how much it will cost. But they are also used as a means of targeting and for control. They are used as a proxy for commitment and they are gamed (i.e. changed for specific ends) when they don’t give the time/cost numbers desired. (This is something Esther Derby discusses recently in her blog, Estimating is often helpful, estimates are not.)

In fact, time estimates show the same range of problems present in the corporate budgeting processes and which has given rise to the beyond budgeting movement.

One direct result of Goodhart’s Law in this context is...

Inflation, the second reason to avoid points based contracts: points are subjective, they are not grounded in time, complexity, function point analysis, lines of code or any other objective measurement. They are in fact like a fiat currency: they are worth what you can buy with it. If people don’t believe in it, or believe the value will change then it will change. Check out rational expectations theory if you want to understand why.

Overtime points can devalue with the result that point scores increase. Actually, I believe the free floating nature of points is one of the strongest reasons for using them but in terms of signing a contract it makes them useless.

Most teams I see work in low points: 1, 2, maybe a 5, rarely an 8, they score 10, 12 or maybe 20 an iteration. One team I saw worked in tens, and scored hundreds each iteration. It was like one of those old Space Invaders machines were the last digit was a hard coded “0”.

The team’s project manager finished planning meetings with an call for the team to work harder next iteration, to reclaim the lost time. Iteration on iteration velocity increased. Inflation was rampant.

Finally there is practicality. As the recent posts from myself and Vasco Duarte demonstrate points, there is still a lot of debate over points. Personally I have come to the conclusion that exactly how you run iterations and count points makes a big difference. While if you agree with Duarte you might as well dispense with points and sign story based contracts.

Then there is the team: only the team which will do the work can accurately say how many points a piece of work will, or did, take; and then only when they have experience of doing the work. So you shouldn’t sign a points based contract unless you have the team in place and they have done some of the work.

Even a relaxed interpretation of that last point should lead you to conclude you should only sign a points based contract when the team is experienced in using points and you have historical data. If you feel you must sign a points based contract then only do it when you have data.

Still, I’d rather you didn’t do it in the first place.

Friday, April 20, 2012

Points: conclusions and hypothesis

As anyone with time to spare will know I’ve recently spent a lot of time thinking, and writing about story points. This was in response to Vasco Duarte’s Story Points Considered Harmful blog from a month or two back. For completeness here are the links:
Some conclusions I draw from this:
  • There is far more work to do on Abstract/Story Points than we, as a community have done to date
  • There are many more nuances to the assignment of points, the breakdown of work and the management of the outcomes than I think I previously realised
  • I must go and see what Mike Cohn actually says about Story Points before I say any more about his approach
  • Stable teams are crucial - but then I’ve been saying this all along
Given all this I’d like to pose a few questions and hypothesis of my own

Q1: When does the correlation between story points and number of cards become stable?

Hypothesis: I would expect a team new to “Agile”, stories and points to start off with erratic point scores and number of stories complete per sprint. Thus I would not expect the correlation to be stable. As a team settles down I would expect points to become stable, then stories completed and thus establish a correlation.

Q2: Is there any serious research into story points out there?

In the same line as my recent post “Agile: Where’s the Evidence?” it would be interesting to know if anyone has examined the use and accuracy of story points. Again, I should seclude myself in an academic library and review the data. But again, I have to find time.

More problematic, I suspect, OK another hypothesis, that some of the reason why story points work - which I listed in part 3 of my posts - will make it very difficult to determine if they are accurate because the thing story points are measuring will change.

Thursday, April 19, 2012

Points 4 of 4 - Breakdown

This entry directly continues from three earlier ones:
Duarte’s analysis, and my response, has got me thinking. And I think it would be useful - to me at least, maybe to some readers! - to explain why I think story points, or rather the “Abstract Points” that I prefer, are still useful, and why I advise teams to break down Blues - stories, possibly User Stories.

Why do I advise teams to break down Blues/Stories?

My background is as a C++ programmer, I worked on financial, telecom, and other systems. A business story, a Blue, would frequently be bigger than a developer could manage in an iteration - particularly if you have a legacy system. Thus I would break Blues down to Whites. (See Blue-White-Red (PDF) if you want to know more about this approach.)

Blues mean something to the business, Whites mean something to developers. I think this situation still holds for many developers in many environments. This has several advantages:
  • Whites are smaller pieces of work, they flow through a system more easily. Progress can be seen, tasks tracked, velocity calculated.
  • “The Business” aka Product Owner/Manager/BA are not always good at delivering small stories, breaking a blue down gives the developer a chance.
  • On some teams the business have been beaten up by development to request really small stories. However these stories lack business value. Because Blues are going to be broken down they can be large enough to have value even if that means that can’t be completed in one iteration/sprint.
  • (Yes, you heard that right) Whites are completed during the iteration, when all the Whites, or the essential ones, are completed then the Blue is completed.
  • Breaking Blues down to Whites is as much a design exercise as it is an estimation and scheduling one. This allows teams to engage in design and create a shared understanding.
  • Breaking Blues down to Whites frequently reveals functionality or assumptions about the Blue requirement which can be removed or postponed.
  • Having the Product Manager/Owner/BA in the room during this break down allows for requirements elaboration and knowledge mining.
  • Work can be rolled from one iteration to the next. I’m very relaxed about carry over work and I think for a new team its almost unavoidable. However doing it this way allows some points to be counted and illustrates what is happening.
(Of course the break down does create some problems: a Blue can only be done when all the Whites, or some done and other cancelled, which mean tracking becomes more complex. It might also break the Lean idea of “single piece flow” but I’m not sure.)

Next, why, given Duarte’s analysis, do I still advise teams to estimate their work?

  • I have seen the breakdown and estimate approach. As detailed previously in one case it allowed a team to forecast to the day.
  • Estimating work allows teams, and individual team members, to raise a warning when work is not understood, defined or involves a lot of risk. For example, a team estimating with planning poker will normally settle on an “average size” of task, e.g. 3 or 5 points. When they suddenly assign 13 or 20 points to a task something is wrong.
  • And just in case the warning is ignored the team, the people at the code face, the people doing the work, have a control mechanism. No matter how much the business or a manager bully a team they can still assign a high point score.
  • Equally, when differences in estimation appears it is a trigger to discussion, to learning, to understanding. This is desirable.
Finally, there is one more reason why I will continue to advise to point their work, and its one I don’t normally admit to but, well Vasco, you win.....

Placebo effect.

Managers, particularly trained project managers, find it alien to not estimate. Actually they are not alone, I’ve seen plenty of developers and testers who think the Kanban craze of not estimating work is nutty. Going through the rituals of pointing and planning poker provides at least the appearance of doing “the right thing.”

Asking these folk to go cold turkey on planning and estimation is tough.

Likewise, asking them to give up Gantt charts can be tough, so we offer them burn down charts. To be honest I find intra-sprint burn-down charts useless. Even the efficacy of pan-iteration burn-down charts surprised me at first. I now see they can be very useful and recommend their use. (Intellectually I prefer Cumulative Flow Diagrams but they are more difficult to get your head around and more difficult for the casual viewer to understand.)

A mature team is, almost by definition, beyond needing placebos. In a mature team I would expect the business to be requesting small stories which do represent value and do fit within an iteration. Thus I would expect Duarte’s analysis to hold up and a mature team might well decide to go without points and use cards.

However, for team at the beginning of its Agile journey I don’t expect these conditions hold.

Finally, for this instalment, I’ve started to wonder about Blue-White-Red again. I’ve long regarded Blue-White-Red as a Scrum/XP hybrid - closer to XP than Scrum if I’m honest. While I’ve been asked to write more about it in the past never have. Over time I have refined my thinking about it. I’m now wondering if Blue-White-Red is actually something more different than I’ve ever appreciated.

Maybe someone who has used Blue-White-Red can answer than one.

Wednesday, April 18, 2012

Story points 3 of 4 - An example

This entry continues from two earlier ones:
I’ve got some (abstract) points data of my own. Not as much as Duarte’s but some. One team in particular is interesting. The development manage said a few months ago “We can deliver to the day.” But actually, when you look at the data the velocity looks quite variable. Whats going on?

Well two things, at least. First, when you average the data out it is no where near as variable - thats what averages do. I’m reminded of the old economists warning: “Do not pay to much attention to one month’s figures [GDP/GNP/Inflaction/etc]. Look at the trend.”

So yes, velocity iteration to iteration changes but over a longer period it is meaningful.

Second, this is a team I regard as stable. I learned a long time ago that if you don’t have a stable team your velocity data is meaningless. The velocity is delivered by the team members, if you change the team you can’t get a meaningful velocity.

While I regard this team as stable when I looked close, looked at the data and dredged my memory, this was not a stable team. One member retired, one member joined, the team was joined by another person to tackle a specific sub-set of work, the team adopted TDD a few months after moving to iterations, later still they tried doing pair-programming.

Somewhere along the line the hardware team joined the iterations, added to the velocity, then, after a while left. It didn’t work as well as hoped. When you look at the data you can see this: alone the software team can have a standard deviation as low as 3.6 on an average velocity of 62 (over 5 iterations) , with the hardware team added that goes to over 17 on a velocity of 60.

(Velocity falls after team expansion is a phenomenon I’ve seen in two other data sets I’ve got. Brooks’ Law doesn’t completely explain this, other factors are at work which I will discuss another day (i.e. when I understand them more fully!))

In other words, the team wasn’t stable. In fact, given all that change I’m surprised velocity was as stable as it was!

I think a third factor was at work. Once a team have put a point score on a card, say they point it to 5. Then there is a mild incentive to finish the card in something that feels like 5 points. Not the strong commitment of Scrum mythology, more a pride in ones own skills, and perhaps, a desire to score points at the end of the iteration.

Fourth: its not just development estimates that are helping the team hit dates. Armed with this data scope can be fine tuned, teams can take decisions on when to do refactorings and so on.

Fifth: once a team has velocity data and can forecast dates it it can negotiate on features and deliveries. This echo’s Duarte’s story but is more fine grained. Of course this won’t help if the end customers/users/clients/stakeholders aren’t prepared to engage.

Given all this I believe abstract points and graphs are helpful, not harmful.

Perhaps one day I’ll be able to publish this data. Its just one team but it shows that velocity and point scoring can work.