I'm amazed at how flawless some people think they are. Judging by the responses I often get to questions, I happen to work at an organization with a handful of people who NEVER make mistakes and know the answer to EVERYTHING. Oddly enough, though, these people seem to always have to work with a bunch of morons who never understand the genius in their presence.
It seems like my job has become that of gradually bringing a lot of these folks down off their high and enlightening people to problems with their reasoning. There seems to be an abundance of overconfidence in IT that "I know what I'm talking about" without and abundance of careful thought about all the options available to us or the inevitable consequences (everything has a down side). The troubling thing is, while there are obviously solutions to make this determination (documentation...), there are really no economical ways to determine if someone has done the careful thought or not in the time scales our projects typically run.
My job now is finding people who have actually thought about the problem (and making this determination is HARD) and exposing their ideas and insights to people who are making arbitrary decisions based on little, flawed, or no information. Put another way, it's all about educating everyone in my sphere of influence so that the entire team builds off of each others knowledge and experience.