OK, that’s not actually true.
I’ve read some good books on lean. In fact, I always have my clients buy Daniel Mann’s “Creating a Lean Culture”.
I confess…I wrote that post title as “click bait” to get you to read this article. But a lot of what’s in many lean texts hasn’t been helpful to me in my work.For example, most lean texts I’ve read get to “takt time” in the first few pages. Do you know that I’ve pretty much never talked with any of my customers about “takt time”? And, for sure, I’ve never, ever calculated “takt time” with or for a client. I talk a lot about creating and sustaining a smooth, consistent, predictable flow of materials and information but never “takt time”. And it’s not because I don’t understand “takt time”…I actually think I understand it better than most texts I’ve read which only tell me that it’s “production at the rate of customer demand”, a concept that’s almost meaningless for most job shop (high mix/low volume) manufacturers. They’re already producing at the rate of customer demand (for the most part) in that they’re never making anything that a customer hasn’t already demanded (for the most part).
Here’s what got me thinking about all this: last week I visited a client organization that’s made up of several separate businesses, each with its own strategy and core processes. There’s some manufacturing. There’s lots of supply chain/distribution/logistics. New product development and customer service are strategic processes. Trust me, the book that tells one how to implement lean across this company doesn’t exist (although, “Creating a Lean Culture” comes pretty close.) And you can bet that this is another of those instances in which the words “takt time” will never cross my lips. If I mention Toyota Production System, it will be to say that much of it doesn’t apply and what does will have to be translated.
On the other hand, we will talk a lot about process variation and how it disrupts flow. And that Lean is all about identifying the sources of that variation and addressing them so that flow is optimized and waste is reduced throughout the process. Right now, I can hear you saying, “But, Rick…at its foundation, that’s what the Toyota Production System and all those books based on it are all about!” Of course, I’d agree. So maybe it’s not that the books are wrong but that practitioners have gotten too wrapped up in the tools (like “takt time”) and still fail to fully understand the importance of the principles and concepts on which they’re based.