Just gotta point out this question is on its own a philosophical question :p
But a question that, I guess, with an answer that is not so readily answered. A question that leads to thought, and more questions. Not to say that all philosophical questions don't have an answer, because personally I find that devastating. A question that brings about the whys, hows, and in what cases/ all cases. This definitely is not a complete answer to your question at all, just to point out some features. But also realizing that these may possibly apply to non-philosophical questions as well.