Taiico Ohno's categorization of major wastes that Lean production relentlessly tries to eradicate:
- Defective Parts; inspection, rework and scrap,
- Overproduction; producing more than what the downstream step or customer can use,
- Inventory; more than what is needed for an effective pull system,
- Motion; searching for tools, parts, etc.
- Processing; additional work due to poor tooling or that exceed a well-considered specification,
- Transportation; movement of parts to and from storage or between distant operations,
- Waiting; for parts, tools, cranes, equipment failures, machines to finish, etc.
Many people add an eight waste, unimplemented ideas.