Today I've spotted once again a question, that I thought I could write an answer to, but now it has already an accepted answer (which I quite like and +1ed by the way). So I am again thinking about the issue under what conditions it would be reasonable or "constructive" to add my new answer anyway. I guess it could in principle be not completely pointless to add a new answer if it
brings in alternative valid points of view or explanations
complements the accepted answer by mentioning additional points
gives more (technical) details about what is already said in the accepted answer
But it often happend to me that when adding a new answer because one or more of the points mentiond above apply, it got no votes which I interpret as it has not been useful for anybody, which makes me feel like a fool. I then think I should at most have left a complementary comment and better delete the useless answer again ...
What do other people think about this?