Cool Backstory Syndrome

[RevBob]

I remember hearing several years back that in a good novel, the author knows much more about the story and the setting than what actually makes it into the book. That extra is by no means wasted; it at least informs continuity and motivations.

This is even more important for an RPG setting, where you don't have a singular experience that is always shown in the same way. Not all games have rails, and even those that do sometimes wander astray.