I just acquired the Tenacious badge but the description is leaving me wondering what exactly I've done to acquire it.
Zero score accepted answers: more than 5 and 20% of total.
Meta Stack Exchange is a question and answer site for meta-discussion of the Stack Exchange family of Q&A websites. It only takes a minute to sign up.Sign up to join this community
Have zero score on 20 percent of your total accepted answers (excluding CW and self-accept) (and 5 times). There is a very important thing about this badge. You have to wait 10 days and if you still have the required conditions, you get the badge. In other words, wait and stay not upvoted.
(Note to all downvoters: This IS the case on Stack Overflow, I don't know if it's a special example or it is the case on all sites (see here, it is the case for Unsung Hero! And see this: Tenacious problem where the asker should have the Tenacious badge but some of the answers are less than 10 days old) And see this. I have a lot of evidence against the "awarded instantly" thing)