It's a good habit to be in. Why bump a thread in less than a day? It just makes your thread go ahead of other threads for no reason. If someone writes a question and 20 people read it and don't know the answer, then 5 hours later, the thread is bumped, those 20 people have to look at it again to see nothing other than "bump". It wastes peoples' time for no reason.

*IF* someone knows the answer, it will be answered. Sometimes, people aren't around and bumping doesn't do any good. I don't agree with bumping anything unless it's been 3-4 days without a response (2 if it's really important). That's my personal opinion. The 24 hour limit was stated as it's a good general rule to follow and will usually be "safe" to do on all forums. In any case, bumping in under and hour is definite grounds for being banned... especially if done more than once after being warned. Again, that's my opinion.