This morning I got a notice that I had earned the "Set Bounty" privilege. According to the list I would need 75 reputation. But I only have 60 at present.
Sounds to me like somebody accepted an answer of yours and then changed their mind.
Fixing this is very tricky. Take this example:
Obviously, the right thing to do is to pull the message out of the inbox, but that will require a fair bit of redesign to keep the process efficient.
One possible solution is to alert people of their new privileges shortly after attaining them, rather than when they attain them.
For instance, we might only notify them when
While notifying someone of a new ability the instant they gain it is nice, I don't think there's much harm in notifying them a day later.
On the other hand, this is a corner case and isn't really important to solve.
The only situation where this is significant is in cases of voting anomoly detection, where several upvotes might be lost. It might be worthwhile pushing these "new ability" notifications only after the voting anomoly process has run.