If your thread isn't approved after a 24-hour period or so, ask a mod why. As long as you don't continually bother them about it (ie. don't go "WHY WAS MY THREAD NOT APPROVED!!!!!!!!!!111111111111 WHY DON'T YOU RESPOND?!!!!"), they won't get ticked off and they'll explain. They're human, after all, so they can't be online all the time, or they can be lazy and not answer for a little while because they're busy or something. Don't repeatedly ask them and they'll (usually) explain.