Why do so many good questions say Topic Closed?

Why do so many good questions get Topic Closed before they even get fully answered?

There’s so many people here that didn’t get a complete answer and then maybe somebody stumbles on the question 6 months later with an answer, but they can’t respond because the post is closed!

This link shows the policy (see link below), but it does not really touch on the fact that great questions are left unanswered or not fully answered. Often another very relevant question or updated answer would be appropriate, but there’s no system for opening a question. What about giving these topics a little more time to mature? Or what if a question get 10 votes to reopen?
http://codex.wordpress.org/Forum_Welcome#Closing_Posts

In comparison, I’ve seen fantastic results on Stack Exchange where experts are always answering with solid information, but I’d like to see the Official WordPress Forum be the go to place! This may sound like a complaint, but I’m trying to help improve my favorite software and community! I’m really thankful for WP and hope to help in whatever ways I can.

Please comment with your experience and thoughts about this AND moderators, please DO NOT close this topic. If it’s closed, I’ll feel like the moderatos are not embracing the community feedback. I tried to bring this up before, but of course it was closed before anyone would respond. 😉