Any activity that consumes resources without creating value for the customer. Within this general category it is useful to distinguish between type one muda, consisting of activities that cannot be eliminated immediately, and type two muda, consisting of activities that can be eliminated quickly through kaizen.
An example of type one muda is a rework operation after a paintbooth, which is required to obtain a finish acceptable to the customer from a paint process that is not highly capable. Because a completely capable paint process for fine finishes has eluded manufacturers for decades, it is not likely that this type of muda can be eliminated quickly.
An example of type two muda is multiple movements of products and inventories between steps in a fabrication and assembly process. These steps can be quickly eliminated in a kaizen workshop by moving production equipment and operators into a smoothly flowing cell.