I don't think the Unsung Hero badge is easy to obtain. In fact I'd like to get it, but I have pretty much given up at this point. It's particularly hard if you're not one of those people who informs the users of the possibility of accepting answers in questions to which themselves have provided answers. There are even some who ask the user to consider accepting their answers.
Perusing through the badges page, one can see that this badge is one of the least awarded ones. This is an indicator that it's not easy to get, even though (I assume) most of them were awarded without the awardees even trying to get them. I have seen one user limiting his answering participation, picking which questions to answer very carefully in order to try to get the badge. I don't think there's anything wrong with this.
Why is it so hard to get this badge?
- People's criteria for voting are very much dependent on the author of the content. If you're known enough or have a high enough reputation, people are more likely to up vote you for the same content than if you were a new user with low reputation. I'm not criticizing this behavior, just saying it happens.
- The criteria are: number of accepted answers with zero votes must be greater than 10 and at least one quarter of your answers must be accepted with no votes. One QUARTER. Doesn't this just look incredibly demanding to you? (Sorry for the lack of justification, I don't know how to argue that it is too much to ask).
- Askers who accept answers and do not up vote are rare. If they know about accepting answers, then they are familiar with SE. This is increases the chances that they are registered users which in turn increases the chances that they will also up vote the answer. Among unregistered users, it's very common to see unfamiliarity with SE.
- Answer acceptance is a greater reward than up voting (not just reputation wise, but also because it visually singles out one answer). Accepting an answer and not up voting it (while being able to up vote) feels more like some sort of undue punishment than a reward.
In a related subject. When we require registration to ask a question, it will be even harder (close to impossible?) to get this badge. Can someone please check how many of these badges were awarded on other sites after registration became mandatory?
In my opinion the badges requirement's should be tweaked or the badge should be deleted (or something like that).