[Off Topic] Watch Out for Kanban-butt
For some reason, lately a lot of people have been discussing and evangelizing Kanban, and it’s starting to annoy me. Applying the Kanban tool as if it were a whole methodology is a mistake. This tool was created and spread by Toyota, decades ago, inside a much larger methodology: the Toyota Production System (TPS), from the great Taiichi Ohno.
As I said in a previous article, agile methodologies share the same foundation. To understand TPS it’s worth going back to the original literature, and one of those sources is the book A Study of the Toyota Production System from an Industrial Engineering Viewpoint, by Shigeo Shingo, published in 1996. In the Preface he says:
Many believe that when implementing a new system, only “know-how” is needed. However, if you want to succeed, you must understand, as well, “know-why”
With the know-how, you can operate the system, but you won’t know what to do if you encounter problems under conditions different from the usual. With the know-why, or “knowing why,” you understand why you have to do what you’re doing, and thus face changing situations.
Specifically about Kanban he says:
The biggest problem I encountered while studying TPS from an Industrial Engineering viewpoint is the fact that it’s often considered synonymous with the Kanban system. Mr. Ohno writes:
- TPS is a production system
- The Kanban method is a technique for its implementation
Many publications are confused on this issue and offer an explanation of the system, claiming that Kanban is the essence of TPS. Once again: TPS is a production system, and the kanban method is merely a means of controlling the system.
Superficial analyses of TPS give special attention to the kanban method because of its unique characteristics. Consequently, many people conclude that TPS is equivalent to the Kanban method.
A Kanban method should only be adopted after the production system itself has been rationalized. That’s the reason this book repeatedly insists on the fact that TPS and the Toyota method are separate entities.
I should add that 90% of Toyota’s excellent management performance was attributed to TPS itself, and only 10% to the Kanban method — a clear demonstration of the greater importance of TPS.
Worth repeating: Shigeo wrote this in 1996. It’s striking that, more than a decade later, we’re still making the same interpretation mistakes.
Just like the Agile Manifesto, the Toyota System has a set of 14 principles, known in the West as The Toyota Way. And the same way it works in Agile, sticking post-its on the wall and running Sprints doesn’t make anything Agile. Following the Toyota method takes a lot more than using Kanban.
To understand Toyota it’s mandatory to understand the Toyota Way, and one of the best books to start with is The Toyota Way by Jeffrey Liker. If you intend to take this seriously, you also need to understand Toyota’s management revolution, narrated in the classic The Machine That Changed the World by James Womack.
If you’re still not convinced, at the conclusion of the chapter on Kanban, Shigeo Shingo himself says:
Kanban systems can only be applied in factories with repetitive production. (…)
Kanban systems are not applicable in companies with non-repetitive project-based production, where orders are infrequent and unpredictable.
The type of production most likely to benefit from Kanban is that which uses common material transformation processes.
A tip: software development is a non-repetitive task. Even so, TPS principles stay very applicable when the know-why is clear.
The Toyota method is more generically known as Lean Manufacturing. The best work adapting Lean to the software world is the book Lean Software Development, by Tom and Mary Poppendieck. Before talking loosely about Kanban, it’s mandatory to read those works; otherwise it’ll just be one more tool doomed to fail, and we’ll end up with a wave of Kanban-butts.
Everything that comes easy goes easy. It “seems” easy to implement Agile. It “seems” easy to implement Kanban. There’s no free lunch. Take things superficially and don’t expect anything beyond mediocre results. That’s how it works.