I just got the Tenacious Badge, and I clicked my way to find out what it was for.
I have read it ten times, and I still don't fully understand what I got it for. Maybe it's just because I'm Norwegian, but still, please, write a better description!
2 years later the description is still confusing:
Zero score accepted answers: more than 5 and 20% of total.
Jeff wrote in a blog comment that it meant:
You have more than 5 zero score accepted answers, and zero score accepted answers make up 20% of your total accepted answers.
You can see why we didn’t include the full text here, I hope.. :)
However the description remains unchanged and is not in any way comprehensible even to native English speakers. Jeff's comment can be rewritten to make it absolutely crystal clear:
You have more than 5 accepted answers with a score of zero, and these accepted answers make up 20% of your total accepted answers.
This is a feature-request.