The description currently reads:
Zero score accepted answers: more than 10 and 25% of total.
The English sentence is really awkward and ambiguous: exactly 25%? >= 25%? <= 25%? it doesn't say (but the correct answer is >= 25%).
Besides that, I think requiring that at least 25% of your total answers should have no votes makes no sense.
Almost all the badges we have (if not all) are there to encourage good behavior. However if I want to get this badge I will have to intentionally try not to get my answers upvoted and the more helpful I was the more difficult it will be. For someone like Jon Skeet, getting this badge will be impossible because he will have to post more than 15,000 extra answers - and all of them would have to be accepted and not upvoted.
This seems a bit backwards to me. However without the 25% requirement (that no one asked for in the proposal thread) this badge makes sense since it encourages answering very difficult and obscure questions, while still being able to contribute to "normal" questions without jeopardizing your work on this badge.
And please change the wording to something more natural:
Posted at least X answers which have been accepted but not upvoted.
Answering part of waffles' answer (his full answer is right below, I accepted it so it shows up to the top):
Take david kanarek for example, he posts lots of answers in the iPhone tag, for example this one, a correct technical answer for a complex iPhone issue. The thing is, for some reason people do not upvote this stuff. Perhaps the iPhone crowd did not discover upvote button, perhaps its the low views, who knows. What we do know is that we want David to keep on contributing to Stack Overflow, so we give him a badge for his efforts.
- Top tags: C#, asp.net, .net, sql-server, sql. They don't really look like unknown and obscure tags.. In fact they are the post popular!
- Now, some examples of accepted answers with zero votes. One, two, three, four.. Most of them are very short and just contain a link. In many cases there are other upvoted answers (but the OP accepted his). Honestly, they don't seem great answers. Murph if you are reading this sorry, I just picked your name randomly - nothing personal - but I wouldn't call him an "unsung hero".
- Top tags: flex, actionscript-3, flex3, actionscript, xml
- Answers: one, two (answered his own question), three, four.. Again in all honesty they don't seem great answers.
- Answers: one, two, three, four.. Again, all seem very "average" answers.
The concept here is to give these "poor users" that participate in tags that are not wildly followed or upvoted or happen to answer less popular questions some extra incentive to keep on making Stack Overflow better.
Did you look at the data before stating this? I manually went through the vast majority of the user profiles who got the badge. Around 75% of them (and that's being conservative, it's probably more) are active only in very popular tags such as
This is not meant to be another badge amongst the 1400 badges Jon Skeet already has, its about giving these users that contribute in a less popular way an incentive to keep contributing.
But it's based on luck, it's not something you can actually work towards. You just have to be lucky, and if you don't get it by the time you have - let's say - 5,000 rep, you will never able to get it. If it's a lottery that you can't even keep participating in after a certain point it doesn't encourage any behavior.
Yes, there are other very luck based badges, but you can keep working towards them until you eventually obtain them. You can't in this case.