Muda

Muda means waste, where waste is any activity that does not add value. Reducing or eliminating muda is, of course, one of the fundamental objectives of any quality-oriented person.

Taichi Ohno of Toyota identified what are called the seven wastes or seven mudas, being the most common form of muda found:

• Waste from overproduction

• Which leads to excess inventory, paperwork, handling, storage, space, interest charges, machinery, defects, people and overhead.
• It is often difficult to see this waste as everyone seems busy.

• Waste of time in waiting

• People may be waiting for parts or instructions.
• Mostly they are waiting for one another, which often happens because they have non-aligned objectives.

• Transportation waste

• Poor layouts lead to things being moved multiple times.
• If things are not well place, they can be hard to find.
• It can aggravate alignment of processes. 

• Processing waste

• Additional effort may be required in an inefficient process.

• Inventory waste

• Excess buffer stocks a whole host of sins, which will be uncovered by gradually lowering inventory (doing it all at once will cause total breakdown!).

• Waste of motion

• This includes movement of people, from simple actions when in one place to geographic movement. Having everything to hand as it is needed reduces motion muda.

• Waste from product defects

• Defects cause rework, confusion and upset a synchronized set of processes.

A simplified view of muda is:

• Wasting time.

• Wasting a consumable resource, such as materials.

• Causing dissatisfaction (including incomplete satisfaction).

Muda is one of the '3Ms': muda, or waste, mura, meaning irregular, uneven or inconsistent, and muri, meaning unreasonable or excessive strain.

See also: