The FAQ says that "...this is a place for questions that can be answered!" But questions are by their very nature often unclear. It is answers that should be precise. Mathematics is in large part the art of making rigorous good sense out of vague questions. If you don't know how to do that for someone's question, you should step aside for someone like Bill Dubuque who can. To close a question right away is to slam the door in the face of those who may have something constructive to offer, even if you don't. Closing amounts to censorship of those who may be able to help. Couldn't you just request clarification from the questioner and move on? Or couldn't you at least wait for a decent period before closing? So what if a poorly posed question just sits there for awhile with no answers forthcoming?
I had hopes for this site as a friendlier, more accommodating alternative to MathOverflow. I suspect that this is partly what was intended. It's no secret that MathOverflow has a reputation for elitismelitism, but now it seems that the very same mindset (same people, I guess) is taking root here too.