• On the content in specific case: First, that it was transformed to a cmnt also sends the message that you did contribute something useful (otherwise it would have been just deleted, not preserved as a comment). So the feedback is not as negative as you might think it is. Would it also work as an answer? Likely, yes. But also note that such decisions might be taken based on the answer in isolation and the style of your answer is comment-like. Would you have written instead, say: "Define your candidate for a norm functions as $d(x,0)$. Verify it is a norm." it's more clear it's an answer. – quid Aug 21 '16 at 19:04