Because I am lazy, here's a blog post I wrote a while ago - October 2007, in fact - yet never finished:
'Burying reader under a dumpload of facts' (I think I stole that quote from someone, not sure who anymore) is the bane of sf/fantasy. One of the banes, anyway. It's a bit difficult to have an outsider's perspective when you're making up the world in your own head.
Then again, that doesn't take cliche into account. The Lord of the Rings Rip-Off No. [Insert Arbitrarily Large Number Here] may well count as being written with an 'outsider's perspective'. In fact, the parts of the regurgitated fantasy world the author invented themselves stick out because those are the only parts the author bothers to explain. Unfortunately, this can be extended to plot and character motivations just as much as setting...
And there's always things like vampires, where authors sometimes even start out by explaining which cliches are true, which are untrue, and which the narrator (read: author) thinks are utterly ridiculous (read: unkewl). (Vulnerability to garlic? Not in MY vampires!)
Annoying though this is, it does speak to a central problem of sf/fantasy, which, come to think of it, is merely an exaggerated version of the Setting Problem all stories have - how do you get all this info across to your reader without annoying them? Which is bad, which is good? Purely, I suppose, good info would be info relevant to the character, and bad info would be info relevant only to the author. But what about info irrelevant to the character, but relevant to the reader?
I guess that's why the Newbie Initiate character is so popular. Too bad they're usually boring as shit.