<p>I used to delete my low (zero or below) scoring answers once someone else got the green check. My premise was that my answer was thought so poorly by the rest of the readership that not one other person felt it worthy of a single upvote. But I don't do that anymore. There is the "<a href="http://meta.stackexchange.com/questions/67397/list-of-all-badges-with-full-descriptions/68258#68258">sportsmanship</a>" badge that one can get by leaving one's low scores up and voting for competing answers. </p>

<p>Another reason I've stopped doing it is that on beta sites, your commitment cannot be fulfilled if you have less than 10 answers + questions, so deleting low scoring answers is counterproductive. And a silly bug I've noticed on beta sites is that if you award bounties that take you below 100 karma, no matter how many badges you've acquired by the end of the private beta week, you forfeit your beta badge (which supposedly only requires 3 badges). </p>