In lean production, waste refers to anything that does not add value to a product from the customer’s perspective.
Taicho Ohno, the
- Overproduction – producing more than the customer orders or producing early (before it is demanded) is waste. Inventory of any kind is usually a waste.
- Queues – idle time, storage, and waiting are wastes.
- Transportation – moving material between plants, between work centers, and handling more than once is waste.
- Inventory – unnecessary raw material, work-in-process, finished goods, and excess operating supplies add no value.
- Motion – movement of equipment or people that adds no value is waste.
- Overprocessing – work performed on the product that adds no value is waste.
- Defective product – returns, warranty claims, rework, and scrap are wastes.
Jay Heizer & Barry Render, “Operations Management”, 8th edition