Monday, October 12, 2009

Memo to self: things I learned at the UK Lean Conference

A few of points I picked up at the UK Lean Conference the other week I made a note of and think are worth recording.

Point 1: There are two kinds of Kanban limits, i.e. or work in progress limits.

The first is what we usually think of when we talk about work limits: how many tasks are we working on at any one time. This might be an limitation of the machinery and process we are using or it might be a limit we impose to manage the work.

The second type of limit is a limit on events. For example, you may decide the supply truck is only going to visit the factory once a day.

Or, to put it another way: decide what you are optimising. What is it you see to minimise? Maximise? or optimise some other way?

Point 2: Sometimes, flow trumps waste, and sometimes, value trumps flow. Or, to put it another way: Value > Flow > Waste

This was mentioned several times, and someone gave the original reference but it was too quick and I didn’t note it down. If anyone has it please let me know, I’d like to read it. Until then, here is my understanding.

When people learn about Lean there is a lot of focus on Waste. The Waste idea is easy to get and clearly makes sense. Then there are seven wastes to think about reducing - or eight if you read Liker in “The Toyota Way” and some talk about a ninth waste and I’ve even heard talk of ten. Anyway, 7, 8, 9 or 10 wastes, its something to get your teeth into and start doing.

But a more important concept in lean is flow. The idea that the path work takes through a system needs to be uninterrupted, smooth, and we should work to reduce the time it takes for work to move from one end of the system to the other.

So, sometimes, waste is acceptable if having waste improves flow through a system.

Then there is value. The idea that all work should deliver value to customers. And sometimes, we can deliver more value if we break flow.

For example: There was once a software development team who would throw away all their most recent work if the company made a new sale. The team worked in short iterations so they were never throwing away more than a couple of weeks work but, if they could make a sale by promising a quick delivery then the team reasoned they would add more value by just aborting the current iteration and starting over on the customers work.

Point 3: Waste breaks down in knowledge work
There seemed to be an emerging consensus that while the waste idea made a lot of sense that it could be carried too far; and in software work, and perhaps knowledge work in general, it lead us down some dead-ends and got in the way sometimes.

Because: knowledge work requires some experimentation and exploration, from a production point of view this could be seen as waste. However in this context it is knowledge creation.

I’m sure I learned other things at the conference but right now these are the things that stick in my mind.

As usual at conferences these points were made and learned more between sessions than in sessions. That said you need the sessions not only to give the conference form but to attract the kind of people with whom you will have these conversations. The sessions and speakers act as a kind of filter (Point 4).