What's the dumbest sidequest idea that's ever been in an RPG?

The quest itself might not be dumb, but in Tales of the Abyss, obtaining Natalia's best move has an insanely small window of availability and requires the player to go somewhere that they have no other reason to go at that point in the game and with no hint that they should go there at that point. Once you see the very next cutscene, it's gone forever. In fact, for a long time players wondered how to get this move and it was ultimately discovered by a player fucking up and going there by accident during the window of opportunity. THAT is dumb.