Lately there have been a number of discussions on the boards on the essence of Lean. Many people have the opinion that Lean is a “focus on waste elimination”. Although I understand how anyone could reach that perspective, I don’t share it. Here’s why.
Waste is the target of front line workers. They have little option to change many of the decisions impacting their work. Production schedules, plant layout and equipment, product design, materials and suppliers are examples of the work elements out of the control of front line staff. But all of these elements can impact the production line through creating variation on the line.
Variation is the leading root cause of waste. to prove this to yourself, consider how much easier your workday would be if only the customers ordered the same product every day. Variation is the target of lower levels of management, as the management team is responsible for all the work elements mentioned above, as well as scheduling labor.
Another key cause of both waste and variation is the concept of unreasonableness, or unreasonable expectations. For example, expecting machines to run reliably for extended periods of time without preventive maintenance is unreasonable, as is expecting top performance from workers who have been working large amounts of overtime for several weeks. Unreasonableness is the target of higher levels of management.
So there are three targets for elimination in Lean, not just one. These three are known in Lean as the Three Mu’s – Muda, Muri, and Mura. I view waste reduction is just one result of properly implementing Lean.
What then is the essence of Lean? More in the next post.