The concept of waste in lean is quite different the generally description of it. In lean manufacturing, waste is any item or endeavor that is spent but that does not contribute to the conversion of raw materials into the product that the consumer is paying for. Waste, according to lean, is not just solid, fluid, emissions, or releases; it can be anything else including inventory, skills, unneeded motion and others which do not add values to the final product and are just not needed by the customer.