I've tried to find the answer to this on several occasions, and haven't been able to. I really want to consider SO a useful tool, and to contribute to the community, but the system is rigged against me.
My first exposure to SO was google searching for an answer to a problem. There were 3 answers (with votes > 0) given for the same question I had... the highest rated (>15 votes) was subtly wrong, the middle one (~10 votes) wasn't really applicable (along the lines of telling someone to buy a new car when they asked how to change the oil), and an unloved +2 voted answer at the bottom was spot on correct and far better than the highest rated solution. I wanted to vote that answer up, so I created an account to do so... only to learn that I couldn't do anything that advanced yet. OK, fine, I'll leave a comment on that better answer saying that it was much better than the top voted answer and solved the particular cases that it failed in. Oh, I can't do that either? WTF?!
So it seems the only way I can participate is to write yet another 0 vote answer that's just a duplicate of, or a pointer to, the better answer. Which is never going to be seen because the better answer has managed to get 2 votes already. Or the next time I have a question I can ask it, and wait for someone to post a snarky answer saying "that was already answered you idiot" maybe with a link to the previous occurrence. Either way seems like a silly exercise in gaming the system just to get enough rep to say that an answer that already existed was a good one.
So I walked away from SO with my problem solved, and some doubts about the community. Repeat a similar experience a few months later. And again a few months after that. And now you're moving into an area I care about, photography, so I'm going to try once more to understand how this system works.
I'm not going to ask you to change the system... I just want to understand the mentality behind this. Can anyone shed some light on why the system is so newb-hostile?