From what I realize, badges are used for promotion and as a sign of recognition of a certain useful activity. However, I cannot understand the purpose of some badges that seem to encourage to lower the quality of the posts, namely:
Peer Pressure
Delete own post with score of -3 or lowerTo me, it's correcting own mistakes that should be rewarded, not posting of nonsense with subsequent deletion. It would make more sense if this badge were awarded if the question initially scored −3 would eventually become, let's say, +3 upon improvements by the author (possibly with the guidance in the comments).
Similar issue with this badge was already raised on SO.Meta: The Peer Pressure badge seems to invite bad posts, is that so?
Unsung Hero
Zero score accepted answers: more than 10 and 25% of totalFrom what I observed, this golden badge is often received by the users who leave comment-alike answers consisting of a couple of sentences which sort of address the question, but are by no means comprehensive or demonstrate ingenuity, hence lack of either positive of negative votes (or approximately equivalent number of both). Quite often users who post such answers target questions from the newcomers with 1 rep point who would post a trivial question, and cannot vote yet.
These answers get accepted simply because OP doesn't know better, doesn't want to show the lack of gratitude or there is no other answers since the question isn't that interesting (or a duplicate altogether).
This would be purely my own observations being an active user for over two years (currently, a moderator) of a relative small Chemistry.SE community. Is there something I fundamentally misunderstand about these two badges, or maybe they have a different effect on other network sites?