A plot mechanism designed to disguise the fact that the writer hasn't closed a plot hole. Often used in lame TV shows that make their money from convincing the audience that they have some deep meaning when in fact they are making it up as they go along.
Lostie, Season 2: I bet the smoke monster is some deep metaphysical representation of the life force that is harnessed on the island!
Lostie, Season 7: Wait, they've all been dead this entire season???