(a.k.a. Poka-Yoke (Japanese) Lean tool for making products correctly the first time.
Comments: When thoroughly implemented Error & Mistake-Proofing create improvements on many different levels. Even the products themselves may be redesigned to minimize errors in their manufacture.
Tooling and processes are often reworked to produce error-free parts or at minimum catch errors before they become significant defects that require rework or become scrap.
Example: One common and popular example of Mistake-Proofing is the design of the VHS video tape player. A videotape will only fully enter a VCR and play if it is placed correctly into opening.