'set-and-forget' originates from modern English, specifically formed by combining the verbs 'set' and 'forget', where 'set' meant 'to put or place' and 'forget' meant 'to cease to attend to or remember'.

'set' comes from Old English 'settan' (to place), and 'forget' comes from Old English 'forgietan'/'forgytan' (to lose remembrance). The hyphenated compound 'set-and-forget' is a recent English formation (20th century onward) used especially in technical and marketing contexts to describe equipment or processes that require one-time setup.

Initially a literal sequence 'set and forget' (put something in place and then forget about it), it evolved into an idiomatic description meaning 'configure once and allow to run automatically without further intervention'.