3 M - Lean Six Sigma Glossary - LSSSimplified (2024)

3 M

In lean philosophy, there are 3 M or the 3 Most Wanted when it comes to inefficiencies in the process. One of the core concepts in lean methodology is the elimination of “muda,” “mura,” and “muri,” also known as the 3 M. These three Japanese words represent three types of problems or issues that organizations can strive to solve for in order to improve their processes and increase efficiency. We need to constantly keep looking for these 3 Ms and eliminate them as and when we find them.

The 3 Ms or the 3 Most Wanted are

1. Muda : It means Waste. Muda refers to any activity or process that does not add value to the customer. Examples of muda include overproduction, waiting, excess inventory, unnecessary motion, overprocessing, and defects. Identify and eliminate them all.
2. Mura : It means unevenness or inconsistency in the processes. It refers to uneven distribution of work across process steps or people causing wait time and bottlenecks. This can also be caused by a lack of standardization, which leads to variations in the process, resulting in inefficiency. This can also lead to employee dissatisfaction. Implement Heijunka to solve for Mura.
3. Muri : It means overburden or overwork caused by a lack of balance in the process. It refers to increased stress on machines or on humans working in the process. Such increased stress can lead to complete breakdown. Avoid Muri by standardized work distribution.

Some literature does refer to the 4^th M – Muchi (Ignorance) and 5^th M – Mushi (Ignoring). However, they are almost the same and its perfectly fine to stick to the original 3 Ms.

Elimination of 3 M

To eliminate 3 M, organizations should focus on identifying and eliminating waste in their processes, creating a standardized process, and balancing the process to ensure that it does not become overburdened. This can be achieved through the use of tools such as value stream mapping, process flow analysis, and standard work. Value stream mapping is a tool used to identify and eliminate waste in a process by mapping the flow of materials and information. Process flow analysis is used to identify bottlenecks and inefficiencies in the process. Standard work is used to establish a consistent and efficient process.