muda mura muri

Toyota has built its production system around eliminating three enemies of Lean: Muda (waste), Muri (overload), and Mura (inequality).
Muda is the direct obstacle of the flow. As written below, there are 8 distinctive types of shedding that lead to waiting times and thus longer delivery times in a process. Simply taking out the molt doesn’t work. There is usually a reason why the mute is there and this reason often has to do with the other two enemies: muri and mura. This means that the three enemies of Lean are interrelated and therefore must be taken into account simultaneously.

The three enemies of Lean can be found in both office and production processes. I even dare to say that they can be found more in office processes than in production processes. One of the reasons for this is that the production processes are visible. Everyone who walks through a factory can see the inventory waiting to be worked on. However, in the office environment, processes are often hidden inside our computers, in mailboxes and IT systems.

Although Lean’s goal is to reduce Lean’s three enemies, it may not be possible to completely eliminate them.
In terms of moving, unless your factory is located next to your customer, there will always be some form of transportation required to get the product to your customer. We should focus on reducing transportation time and costs as much as we can, but a 100% reduction is not realistic.
The same goes for muri. There can always be a time when machines or people have to put in that little extra effort or time to make sure customer demand is met. There is nothing wrong with this when you can get a large order for additional products or gain a new customer. The problem exists when you expect this from your machines or people all the time, to the point where a machine burns out or a colleague burns out.
Finally, even mura cannot always be reduced to 100%. When you produce different products, they may require different materials, a different way of working, or even different lead times. This is even more true in project work, where every project is different, or in the financial world, where a financial report is due at the end of each month.

The following three articles explain in more detail how we can find and remove the three enemies of Lean from our processes, here is a brief description of what you can expect:

Table of Contents


Waste can be defined into eight types, 7 defined by Toyota and ‘unused skills’. These are: Defects, Overproduction, Waiting, Unused Talent, Transportation, Inventories, Movement and Excess paperwork. As a mnemonic device, the first letters of these residues form the acronym DOWNTIME.
There are numerous tools available to identify and remove waste from your process, including Poke Yoke, Kanban, Takt Time, SMED, and One Piece Flow. However, the most common tool that helps improve productivity by eliminating the 7 wastes is 5S. In the article How to find Muda (waste) in your process, each of the waste types is described and linked to the tools that can be used to eliminate them systematically.
Muda means futility uselessness waste, although more broadly it refers to the seven common types of waste seen in business.

  1. Defects in the final product
  2. Time lost due to waiting processes
  3. Non-essential movement
  4. Excess inventory of materials or equipment
  5. Excess production
  6. Redundant processes
  7. Unnecessary transportation or handling of materials or products


Overhead can result from Mura and removing too much Muda (waste) from the process. When operators or machines are used more than 100% to complete their task, they are overloaded. This means breakdowns when it comes to machines and absenteeism when it comes to employees. To optimize the use of the machines and ensure that they work properly, preventive and autonomous maintenance can be implemented. To prevent employee overwork, safety must be at the center of all process designs and standard work initiatives. For more information on Muri, go directly to the article: Finding Muri (overload) in your process.


The gap can be found in the fluctuation of customer demand, the process times per product or the variation of cycle times for different operators. In low volume, high product variation production environments, flexibility is more important than in high volume, low product variation environments. When Mura is not reduced, the chance of Muri and therefore Muda is increased. Mura can be reduced by creating openness in the supply chain, changing product design, and creating a standard job for all operators.


What is Muda Mura and muri?
Muda, mura and muri are three types of useless actions that negatively affect workflow, productivity and ultimately customer satisfaction.

What are the 3 M’s of Lean?
Muda, Muri and Mura
Muda, muri and mura are called “the three M’s”. Together they form a dissonant triad. The three M’s must be removed to create a sustainable lean process.

What are the 7 types of Muda?
The 7 forms of muda
Waste of overproduction (largest waste)
Waste of available time (waiting)
transportation waste.
Waste from the processing itself.
Waste of stock at hand.
Movement waste.
Waste from the manufacture of defective products.

What is this kaizen?
Kaizen is a Japanese business philosophy that focuses on gradually improving productivity by involving all employees and making the work environment more efficient. Kaizen translates to “change for the better” or “continuous improvement.”

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By Aditya

Hi, I’m Aditya Sharma, a professional blogger from Gurgaon, India and I launched this blog called aadityacademy on July 2021. is a mechanical Project-oriented platform run by Aditya sharma and I got the motivation to start aadityacademy blog after seeing less technical education information available on google.

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