This is partly related to Remove the 25% requirement from the “Unsung Hero” gold badge question.
I ran some queries on odata for my work on Stack Overflow, and I have found that my statistics are the following ones:
Accepted answers: 148
Zero score accepted answers: 36
Percentage of total: 24,3%
I probably fit the idea of the Unsong hero badge, as I've mostly been active in drupal questions, from when it only had around 200 Questions until now.
To get the badge I could either try to get one of my accepted answers downvoted once, that would give me a 25% accept rate; I could also delete 4 of my accepted answers with 1 or more score. That would also give me the badge, but this just seems wrong: You are actually encouraging me to either try to get a down-vote on a good answer, or delete good answers.
So, should I delete good answers to receive a gold badge?
It's not that I care much if I get a badge or not, it's only a badge after all and not why I spend time on Stackoverflow anyways. But it's not ideal [read: problem] that I'm encouraged to delete accepted answers or try to get downvotes to achieve a badge.