Questions are a very important part of being an efficient programmer. It allows us to communicate with others to gain a better understanding our new concepts. A good question will allow not only you to learn and grow, but for others who have similiar questions to also learn.
A good question is clear and concise. It will be well written and have room for discussion. Such as this question. https://stackoverflow.com/questions/111102/how-do-javascript-closures-work The question is clear and to the point while explaining enough for a user to be able to answer well. It was a question that could be approached in many ways. So this question allowed people to have an open discussion and express their ideas behind the concept.
A bad question makes you wonder what the user is asking or why they are asking this. Such as this question. https://stackoverflow.com/questions/27894144/how-to-block-adblock This was a strange question that seemed more like the asker was trying to get free work. The ads for his websites were getting blocked so he requested for someone to figure out what he could do to stop this. He dumped some code in that I was not completely sure it was for. This was overall a bad question where even the question was hard to understand.