Muda: stands for waste of time, resources and money. Taiichi Ohno originally categorised wastes in 7 types of Muda inside the Toyota Production System: Transport, Inventory, Motion, Waiting, Overproduction, Over-processing, Defects.
Mura: stands for the waste of unevenness or inconsistency. Mura is at the origin of wastes described by Muda, because an erroneous demand readings drive unfair demand on processes and people creating that way unwanted inventory and other wastes. This concept stands at the origin of Just-In-Time technique.
Muri: stands for the waste of overburden that is creating unneeded stress on employees and processes. They are caused by Mura and other failures of the system. Just as Mura, Muri is also the cause for …show more content…
At home he began to experiment new systems and procedures that would allow to minimise wastes and inventory. He started to group workers into teams with a team leader rather than a foremen. Each team was given a set of assembly steps with the objective to work together on how best to perform the necessary operation. Once the teams managed to run smoothly and got used to the assembly tasks he periodically organised team workshops where the members proposed collectively ways to improve the operations and reduce further Muda wastes in the entire value stream. Today these workshops are often called Kaizen Workshops where kaizen, a Japanese term, stands for the continuous, incremental improvement process. As a matter of fact the lean organisation management system used by organisations today is based on the permanently continuous improvement of every organisational function. To further eliminate Muda wastes, Ohno concentrated on Mura. As described before, it implied the correction of the processes that were not following the actual demand and stocked output into inventory. The verticalised supply chain system, typical of the mass production approach, could reach even 70% of in-house production, created many problems for a fast growing Toyota. Suppliers had no incentives to suggest improvements