If they can find any fault in a question or answer they will take the opportunity to do so.
If you give a correct answer but don't include a significant amount of explanation, it will be marked down.
Often times I see perfectly valid questions and people refuse to answer them but will only respond with a comment.
I just wanted to try to help some people. I don't have time to write Wiki articles or deal with assholes who have nothing better to do than to do than try to find fault with a question or answer.
Also, a lot of the time the answer is to use some library or module and you can get attacked for even acknowledging that modules exist.