These communities help all of us. I've learned a lot by helping people figure out solutions to problems they were experiencing. If all you learn is what you experience, you will learn slowly; but by being able to learn form others' experiences, I've learned much faster. Many times I've encountered a "new" problem in or systems and been able to fix it staight away because I had helped someone else diagnose and/or fix it in their own. It really made me look like more of an expert than I am to be able to pull the solution to a new problem off of the top of my head.