Lean, Toyota, and how it relates to agile.

I like to read non-software-development books from time to time, and during my holiday vacation, I read “The Toyota Way to Continuous Improvement: Linking Strategy and Operational Excellence to Achieve Superior Performance”.

What? Doesn’t everybody relax by reading books about different organizational approaches and business transformation during their holidays?

I highly recommend the book if you are interested in agile processes in the abstract; there’s an interesting perspective that I haven’t been seeing in the part of the agile world I’ve been paying attention to. 

I will note that there are a number of people who have explored and written about the overlap between lean and agile, so I don’t think I’m breaking ground here, but there are a few things that I think are worth sharing.

Value stream mapping

Part of my definition of “being agile” involves change; if you aren’t evolving your process on an ongoing basis, you aren’t agile. I’ve spent a lot of time looking at processes and can now look at a team’s process and have a pretty good idea where they are wasting time and what a better world might look like.

Unfortunately, that isn’t especially useful, because “Do what Eric says you should do” is not a particularly good approach. I don’t scale well, and I have been wrong on occasion.

Shocking, I know.

It also removes the tuning to a specific team’s needs, which is pretty important.

I do know how to teach the “determine an experiment to try during retrospective” approach, and have had decent luck with that, but teams tend to go for low-hanging fruit and tend to ignore big opportunities. Just to pick an example, you can experiment your way into a better process for a lot of things, but the project build that takes 20 minutes and the code review process that takes 8 hours is now dominating your inner loop, and those are the things that you should think about.

I don’t currently have a great way to make these things obvious to the team, a way to teach them how to see the things that I’m seeing. I’m also missing a good way to think about the process holistically, so that the big issues will at least be obvious.

Enter value stream mapping, which is a process diagram for whatever the team is doing. It includes the inputs to the team, the outputs from the team, and all of the individual steps that are taken to produce the output. It also typically includes the amount of time each operation takes, how long items sit in a queue between steps, whether there are rework steps, etc. Here’s a simple diagram from Net Objectives:

The times in the boxes are the average times for each step, and I think the times underneath the boxes are the worst cases. The times between are the average queue times. We also show some of the rework that we are spending time (wasting time) on.

Given all of this data, we can walk all the boxes, and figure out that our average time to implement (ignoring rework) is about 266 hours, or over 6 weeks. Worse, our queue time is just killing us; the average queue time is 1280 hours, or a full 8 *months*. So, on average, we can expect that a new request takes over 9 months to be deployed. We can then look at what the world would be like if we combined steps, reduced queue sizes, or reduced rework. It gives us a framework in which we can discuss process.

This is a simple example; I’m sure that the real-world flow also has a “bugfix” path, and there is likely a “high-priority request” section that is also at work.

I’m also interested in the details inside the boxes. We could decompose the Code box into separate steps:

  1. Get current source and build
  2. Write code
  3. Test code
  4. Submit code for code review
  5. Handle code review comments
  6. Submit code to gated checkin system

Each of these steps has queue times between them, there are likely rework loops for some of them, and the “test” step likely varies significantly based on what you are testing.

Coming up with a value stream mapping is typically the first thing you do with the Toyota approach. I like the fact that it’s a holistic process; you cover all the inputs and the outputs rather than focusing on the things you know about.

I have not tried doing this for a software team yet, but I find the approach very promising and hope to try it soon. I’m especially hoping that it will highlight the impact that big organizational systems have on team agility.

Implementing an improvement

The continuous improvement approach used by Toyota is know as PDCA (either plan-do-check-act or plan-do-check-adjust). Here’s a more detailed explanation of “plan”:

  1. Define the problem or objective
  2. Establish targets
  3. Understand the physics (use 5 whys to figure out what is really going on).
  4. Brainstorm alternatives
  5. Analyze and rank alternatives
  6. Evaluate impact on all areas (this is a “what could go wrong?” step)
  7. Create a visual, detailed, double-ended schedule

I like that it’s organized into steps and overall focuses on the “let’s think about this a bit”. That is good, and I especially like #3 and #6.

On the other hand, agile teams who aren’t used to making changes can easily get stuck in analysis paralysis and can’t actually agree on something to try, and a detailed set of steps could easily make that worse. I’m more concerned that they try *something* at the beginning rather than it be the absolute best thing to try.

So, I’m not sure about this one yet, but it is interesting.

Organic vs Mechanistic

In the book, the talk about two ways of implementing lean. The organic approach is close to the Toyota approach; you send a very experienced coach (sensei) into the group, and they teach the group how to do continuous improvement and stick around for a while. This gives great results, but requires a lot of work to teach the team members and reinforcement to make sure the whole team understands that continuous improvement is their job. It is also sensitive to the environment the group is embedded inside; some groups had made the transition but it didn’t take because management didn’t understand the environment it took to foster the improvement in the first place.

I’m sure that seems familiar to many of you trying to do agile.

The mechanistic approach comes from the Six Sigma folks. It focuses more on top-down implementation; you train up a centralized group of people and they go out across the company to hold Kaizen (improvement) events. That gives you breadth and consistency across the organization – which are good things – but the results aren’t as significant and – more importantly – teams do not keep improving on their own.

As you might have figured out, I’m a big fan of the organic approach, as I see it as the only way to get the ongoing continuous improvement that will take you someplace really great – the only way that you will get a radically more productive team. And I’ve seen a lot of “scrum from above” implementations, and – at best – the have not been significant successes. So, I’m biased.

Interestingly, the book has a case study of a company that owned two shipyards. One took an organic approach and the other took the mechanistic approach. The organic approach worked great where it was tried, but it was difficult to spread across that shipyard without support and it was very easy for the group to lose the environment that they needed to do continuous improvement.

The mechanistic shipyard had not seen the sort of improvements that the organic one saw, but because they had an establish program with executive sponsorship, the improvements were spread more broadly in the enterprise and stuck around a bit better.

The consultants said that after 5 years is was not clear which shipyard had benefitted more. Which I find to be very interesting in how you can do something organic but it’s really dependent on the individuals, and to make something lasting you need the support of the larger organization.

The role of employees

In the Toyota world, everybody works on continuous improvement, and there is an expectation that every employee should be able to provide an answer around what the current issues are in their group and how that employee is helping make things better.

That is something that is really missing in the software world, and I’m curious what sort of improvements you would see if everybody knew it was their job to make things better on an ongoing basis.

The role of management

One of the interesting questions about agile transitions is how the role of management evolves, and there are a lot of different approaches taken. We see everything from “business as usual” to people managers with lots of reports (say, 20-50) to approaches that don’t have management in the traditional sense.

I’m a big believer in collaborative self-organizing approaches, and the best that I’m usually hoping for is what I’d label was “benign neglect”. Since that is rare, I hadn’t spent much time thinking about what optimal management might be.

I think I may now have a partial answer to this. Toyota lives and breathes continuous improvement, and one of the most important skills in management is the ability to teach their system at that level. They have employees whose only role is to help groups with continuous improvement. I think the agile analog is roughly, “what would it be like if your management was made up of skilled agile coaches who mostly focused on helping you be better?”

Sounds like a very interesting world to be in – though I’m not sure it’s practical for most software companies.  I do think that having management focusing on the continuous improvement part – if done well – could be a significant value-add for a team.

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