Reset Button

The Reset Button effect is a notorious issue with in the fictional television series Star Trek, especially in later series such as Star Trek: Voyager, wherein any sense of progression through a chain of episodes is lost. Regardless of what happens in the span of one episode, by the end of that episode, everything is as it was at the beginning.

This has been abused to a great degree in time travel episodes, where circumstances have gotten so bad that the ship itself has been destroyed (Year of Hell, for example), but somehow at the end, time reverses and the tragedy is averted.

(But the idea of a return to the status quo ante is not original to Star Trek; Shakespeare scholars have recognized it as a regular device of his comedies, and it is in fact a standard literary device in general. It is also easily discovred in most situation comedies ("sitcoms"), with Gilligan's Island being a particularly notorious example: nothing the castaways do jeopardizes the continuation of the series, as nothing they do actually suceeds in getting them off the island.)