For an eye-opening read, check out the comments on Reddit. Amusingly enough, someone chose the title of this post as Why Stack Overflow sucks. My favourite from one relix:
I've answered exactly 1 question1 question. It was the only correct answer to that question, but it didn't get any votes and didn't get selected as the answer. Instead, the wrong answer was selected and got all the brownie points.
That was the moment I decided never to waste time on Stack Overflow again. Why even bother.