Of course they're many reasons why one wants to answer the question and of course this is really personal. So, you probably have already known the answer before you get into here. Let's see if your answer is stated here. If no, please share yours. :)
- To prove that you're better or powerful or knowledgeable (or whatever you would like to call) than the one who asks the question
- To convince the one who asks questions that your answer is the correct one
- To share your answers to the who asks the questions so that 2 of you can learn together
- To guide the one who asks the question to get the answer by themselves.
- To fulfill your own purpose such as being told by your boss to do so and etc.
You probably haven't realize that the ultimate purpose of answering question is NOT to influence the person who ask the question but at the same time to help them to get the answers that they want.
However in reality, as long as we answer a question and no matter what, you will influence the decision or the thinking of the person who ask a question. So in other words, you can't answer the question at all ultimately. So you may ask, what is the purpose of answering question if we can't answer the question?
It is very clear that the purpose of answering question is not really to help others but yourself. This is because no matter how hard you try, you will end up influence the decision of another person. To completely avoid that, you must NOT know the answer and start answering the question for yourself. In short regardless of whether you're answering for yourself and for somebody else, the purpose of answering question is always the same which is:
In other word - when someone asks you a question, you should only answer a question that you don't know and tell the answers to him by answering to yourself.
p/s: I know this may seem confusing and a lot of you may disagree with this. Let me know if you have any comments.