Muda (Japanese term)

Muda (^?) is a Japanese word meaning "futility; uselessness; wastefulness", and is a key concept in the Toyota Production System (TPS) as one of the three types of deviation from optimal allocation of resources (the others being mura and muri).Waste reduction is an effective way to increase profitability. Toyota adopted these three words beginning with the prefix mu-, which in Japan are widely recognized as a reference to a product improvement program or campaign.

From a customer's point of view, value-added work is a process that adds value by producing goods or providing a service that a customer is willing to pay for. However, muda is any process that consumes more resources than needed, which causes waste to occur.

Muda are broken down into two types namely:

Muda Type - I : The non value added activity for end customer but it is necessary.

Muda Type -II : The non value added activity for end customer which are not necessary. It is targeted to eliminate this type of wastage.

Type-I are usually hard to eliminate because although it is classified as non-value added activity, it is not necessarily muda. For example, the quality inspection process for critical process is needed at car assembly, to ensure the car quality and fulfill safety standards before sending it to the end user; however, from customer point of view, these actions are deemed unnecessary and do not contribute to the assembly process which add values or to the car assembly.

Type-II are non value added activities which contributes to waste and incur hidden costs. Toyota Production System identifies the wastages that occur and group them into 7 major categories.

One of the key steps in Lean and TPS is the identification of which steps add value and which don't. By classifying all the process activities into these two categories it is then possible to start actions for improving the former and eliminating the latter. Some of these definitions may seem rather idealistic, but this tough definition is seen as important to the effectiveness of this key step. Once value-adding work (actual work) has been separated from waste, then such waste can be subdivided into 'needs to be done (auxiliary work) but non-value adding' waste and pure waste. The clear identification of 'non-value adding work', as distinct from waste or work, is critical to identifying the assumptions and beliefs behind the current work process and to challenging them in due course.

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