Sometimes I misunderstand what a post is asking for and I answer it wrongly, and when I realise my error, I can't delete the post.
I know that a better reading of the thread would prevent me from making those stupid mistakes, but errors sometimes happen. I don't think I'm an impulsive poster at all, usually I don't start typing an answer if I'm not sure what the poster is asking, or if I'm not sure that my answer will be useful, and I read my answer a couple of times before clicking the "post" button, but sometimes you can't avoid making a mistake...
It's true that I can edit my post and correct my answer, but what should I do when I misunderstood the question, and I can't answer properly to the real question?
I'm aware that a delete button could cause issues with people deleting answered or ancient posts, but what about having say a couple of grace minutes after posting an answer to delete it if I realise I misunderstood what is being asked?