It probably means they don't know the answer, ever think of that?
Probably because no one knows the answer or haven't had the time to read all of the questions. If you need an answer, just type the question in the "Search" box and it will bring up several web sites to help you with your topic. Good luck!
In my opinion, most of the time it's because not enough details were given to answer a question.
Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them