Waste, in “Lean” terms, is any activity that does not add value to a product, costs money and resources, and earns nothing for a business. From operating losses to missed opportunities.
Would you pay for a meal at a restaurant that was prepared by mistake? Would you purchase a product and pay an extra cost for a feature you didn’t ask for? Would you pay storage fees for a product you bought before it arrived? Probably not.
Similarly, the eight wastes in manufacturing ("DOWNTIME") are:
DEFECTS: The defect waste is defined as the loss of value to scrap, repair, or rework a product that deviates from specifications.
OVERPRODUCTION: Producing more than is needed, faster than needed, or before it’s needed.
WAITING: Caused by inconsistent work methods, lack of proper equipment or materials, long setup times, low man/machine effectiveness, poor equipment maintenance, or skills monopolies.
NON-UTILIZED TALENT: Refers to underutilizing or not properly engaging employees in a process. This could take the form of employees performing unnecessary work when their talent could be utilized in activities that add greater value, or not utilizing employees’ critical thinking abilities and feedback in processes.
TRANSPORTATION: Any material movement that doesn’t directly support immediate production. An improper facility layout, poor production planning, and poor scheduling can generate transport waste.
INVENTORY: Any supply in excess of process requirements necessary to produce goods or services in a Just-in-Time manner.
MOTION (MOVEMENT): Any movement of people that doesn’t contribute added value to the product. Motion waste is often caused by ineffective plant layouts, lack of visual controls, poor process documentation, or poor workplace organization.
EXTRA PROCESSING (OVER-PROCESSING): Any redundant effort in production or communication that does not add value to a product or service. Waste includes endless product or process refinement, excessive information, process bottlenecks, redundant reviews and approvals, and unclear customer specifications.
There are many techniques to help the identification and elimination of waste; however, within lean manufacturing we wish to prevent them from being needed in the first place.
Prevention of defects is achieved through several different techniques from automation or through “error-proof” devices preventing the process from running or highlighting the defect for action.
We also implement standard operations procedures (SOP) and training to ensure that the correct methods are undertaken and standards achieved.
Unbalanced processes are a cause of waiting in the process flow if one process takes longer than the next. Balancing the flow is key to minimizing the waiting waste.
Empowerment of teams to solve and prevent their own problems. By harnessing the talents of employees, a company can quickly and efficiently prevent the occurrence of waste.
George, M Upton, M Price, M (2002), "Lean Six-Sigma", Mc Graw-Hill, NY