Fail-Safe vs. Fail-Proof

A discussion on the English Language & Usage Stack Exchange about things that can still be useful even if they longer function properly, such as escalators and moving sidewalks, included several intriguing expressions involving partial failure. Graceful degradation refers to the ability of a computer or network to maintain limited functionality even if part of the system fails to work properly. Similarly, fail-safe is not the same as failproof; the latter describes something “incapable of failure,” while the former describes something that won’t cause damage even if it does fail. This is part of a complete episode.