I had a bounty here, and there were some good answers, but no answers I think worthy of a bounty. I featured a bounty on the question as it did not receive any answers prior to. What should I do with the pending bounty? Seeing as I already lost that rep, should I still award it to one of those answers because that rep (or half of it) will be lost forever?
As things stand now, no answer would get it automatically either (the recipient answer would have to have a score of at least 2).
If you don't think any of the answers are worth it or the answers are bad in general, don't award it. The whole point of a bounty is to encourage a better answer. If you didn't get one but awarded the bounty anyway, you'd essentially be encouraging a subpar answer.
Now, that said, if you didn't get exactly what you were hoping for, but you got an answer that's pretty good anyway or it helped you out, feel free to reward that user with some rep.
There are no strict rules here. :)