There's something I see pop up from time to time, more often with inexperienced Game Master of Roleplaying Games than with those who have been around the block. It has to do with plotting a game. While this might work fine with a tournament game where the goals of the characters are defined in advance, it rarely works out well in campaign games. This tends to be the truth of it because of how plotting limits the range of choices players can make and affect through their characters.
The fewer choices that a plotted game allows the players to make, the more akin to a board game such a game becomes. Once players realize they have limited choices to make, the more they feel that their characters are merely pawns in a game where destiny is a foregone conclusion. While it is possible to roleplay those situation in-game as if the characters do not have fore-knowledge, the players are not making meaningful choices that can affect the outcome of the game in ways that are not predetermined. This goes against the grain of most roleplaying games, at least in common campaign formats.
For tournaments and one-shot convention or gameday games, this can be the norm and that's all well and good, particularly since in such structured play winning or losing the scenario is often understood to be possible. But for campaign roleplaying games there is rarely the intent to have winners and losers. Each moment of roleplaying games is meant to be its own reward and players are, under ideal conditions, allowed to glean as much from the experience as can be garnered. In campaigns, once the players feel that their characters are merely pawns in a prewritten story, they will become divested of the primary motivations inherent behind a roleplaying activity. At that point, we might as well break out a board game and remove the pretense that meaningful choices are actually possible at all.