Mistake-proofing and fool-proof devices (poke-yoke) made by designing parts, processes, or procedures in a way that mistakes cannot physically or procedurally be possible. Mistake-proofing commonly refers to the use of fail-safe devices in machine operations that detect or prevent defects and insure quality. This is the key ingredient that is added to automation to yield autonomation.
In a lean culture errors are a learning experience; the cause is learned and eliminated. People are not blamed for errors in a lean culture – processes are. In a lean culture people are known to become careless, due to fatigue, lack of attention and any number of other causes. A good lean culture recognizes they need to have simple cost-effective systems to prevent such lapses from affecting quality, and designs them into every process.