Originally, the bounty system was strongly linked to "accepting" an answer:
There are three possible outcomes:
You accept an answer. The bounty is subtracted from your reputation,
and awarded to the answerer.
You do not accept an answer. Any answer that was a) provided after the
bounty period started and b) has 2 or more upvotes is automatically
accepted after 7 days. The bounty is subtracted from your reputation.
The answerer is awarded half the bounty amount (unless it’s your own
answer, see #3 below).
You accept your own answer. The bounty is subtracted from your
reputation.
Note that all bounty awards are immune to the daily
reputation cap, of course. Also, a bounty accepted answer is permanent
and cannot be undone. The traditional accepted answer check is
“glowing” to indicate that this is a special kind of accept.
This was... Pretty awkward. If you didn't get an answer you were happy with, you were stuck. If someone posted a better answer later, you couldn't accept it because your accept-mark was permanently affixed to the bounty winner. If you accepted your own answer, everyone hated you.
So after some extensive discussion, the bounty system and accepted answers were unlinked:
I’m happy to announce that we’re improving the bounty system to
address (almost) all of these issues. As of now:
- Any user with sufficient reputation can start a bounty on any question
- A question may have multiple bounties, though only one active bounty
is allowed at any given time.
- Bounty awards are no longer tied to
accepted answer in any way.
Practically and philosophically, this makes far more sense. The "accept" feature was always supposed to be optional - there's no pressing need within the system for any answer to be accepted on a question, ever: unlike many other forum or Q&A systems, the community is able to select the best answer by voting, leaving acceptance as merely an extra indicator of suitability for the asker's specific needs.
Yes, it's usually appropriate for the asker to accept an answer. But, this is his decision to make - if he doesn't want to, nothing breaks. If he decides to offer - and even award - a bounty, that changes nothing.
This is the symmetric case to the grace period introduced some months ago, where an accepted answer gets automatically the bounty after both the bounty period and the grace period have elapsed.
No, no it's not. There are a handful of rules in place to automatically award half of the bounty amount in situations where the person who offered it fails to award it. These are in place to make the most of failure, and draw on what little information is available from votes and the accepted answer. So bounties and the accepted answer are connected only when:
- The bounty isn't awarded by the person who offers it.
- The asker accepts an answer during the bounty period.
- The answer isn't written by the person offering the bounty.
This is an extreme edge-case - and even when it occurs, nothing stops the asker from changing the accepted answer after the fact, or indeed removing it entirely.