Lean success at companies today is not hindered by a lack of tools, nor the capability of the tools they have. What is really behind companies that succeed at sustained lean implementation is the level of thinking driven by lean principles and rules. Thinking is powerful in changing an organization. Thinking drives behaviors. Behaviors drive action. Action drives results. No tool can fix poor thinking.
To illustrate this point, consider the kanban card, a major tool in many lean transformation efforts since the 1980s. The concept is pretty simple. A downstream process uses parts from an upstream process. As each part is used, a kanban card is removed and sent back to the upstream process. When a predetermined number of cards accumulates at that upstream process, production replenishes the stock used by the downstream process.
Now let's test the thinking. Does the upstream process operator look at the downstream process as his customer? If the customer-supplier relationship is not clear to both parties, then there is no compelling reason to fill that kanban. There is much greater reason to stay busy producing whatever is easier. Is the kanban card a suggestion, a request or just a piece of paper?
If the kanban card is a suggestion, you get one behavior. If it is a specific request, you get a very different behavior. So a fundamental principle behind kanban is the objective of explicitly linking a customer to a supplier through a formal request. Without that objective clearly understood, all we have is a piece of paper.
Why is it so important to follow that request exactly, even accepting downtime because the operator doesn't have a request? The conventional answer is that producing without that request is overproduction that increases inventory and generates waste.
True lean thinking sees beyond that to an even greater reason. By not producing, we have exposed a problem that can be engaged as an opportunity to make the process even stronger. So a most fundamental principle is that kanban is not an inventory and material flow management system. It is a tool for systematically exposing problems in our process as they occur. A change in thinking produces very different behaviors, and ultimately very different results.
One look at the kanban card in light of lean thinking helps those using it understand how and why it works, because they see it and understand it as a request, not a card. It is a method to connect a customer to a supplier. But most companies implementing kanban systems are not successful at getting the users to understand how and why the tool works. The most common excuse-it is too hard for our people to understand-stands in stark contrast to the simple concept.
You can read about the tools and techniques of lean in any book. You can delegate the application and implementation to just about anyone. But you cannot succeed without internalizing the principles of lean throughout all of management, and using that thinking to guide the implementation, daily decision making, problem solving, managing and coaching.
If you have ever visited Toyota, or other world-class manufacturers, you will easily spot several specific ideas that you could go back and implement. However, because there are so many visible examples, we think the difference in performance is explained by what we see. What we fail to grasp is why all those ideas and solutions were created in the first place. In pursuit of those ideas is where lean thinking comes to life. Lean is not about what we see; lean is about how we think.
Whether you agree or disagree, Jamie will welcome your comments. Contact him at firstname.lastname@example.org.