Zero Defects

The term zero defects refers to the goal of achieving output from a process with no defects. It was introduced by the quality guru Philip Crosby, but is now used both by practitioners of total quality management, or process improvement, such as the Six-Sigma approach, and by practitioners of Lean Manufacturing. The Six-Sigma approach involves the aggressive reduction of process variation to the point where as little as 3.4 parts per million are defective. The Lean Manufacturing approach has evolved out of the Toyota Production System, and uses techniques like mistake-proofing (Poka-Yoke) to reduce the occurrence of defects to near-zero levels. This often involves 100% inspection of the process material that occurs early in the process. Reconfiguring the process to achieve just-in-time product flow is central to this approach as well.

Zero defects management is based on the premise that it is better to detect problems before they cause accidents or product defects. Airlines must use a zero defects approach to maintaining and flying their planes. Hospitals would like to achieve zero defects for medication errors, or for infections. Administrators would certainly want zero accounting errors, since their presence could adversely affect the financial condition of the company.