Running a game is like opening a forum thread.
You already have your "perfect" idea.
BUT other people also have their "perfect" idea. (Heck, some people might show up in another language altogether... Okay, probably not. 0w-b )
So instead of where you want thing to go, it goes to every other place but that.
Sometimes you get to learn something out of it though.
Self-reflection, whether by self or accidentally from others, is a good thing. 0w0b
(As for topic: Well, what's more FUN for ME? To the extent of not bothering other people of course.
An RP session about janitors in a recycle depot can be made fun too, if you have the right mindset for it with the right players. Though that probably won't be heroic.)