I have put bounties on my question Names of the electromagnetic units in SI, first for 50 points and now for 100 points. In the process, I have lost my reputation to edit community wiki. I have even lost my reputation to set bounties and even to comment on other posts. However, I am not receiving any answer during the bounty period. I cannot understand why I am not getting any answer during the bounty period.
You already received an answer, and moreover you accepted it, meaning you're (reasonably) satisfied with it. That may deter other users from posting another answer.
Otherwise, a bounty is just like an advertisement in the real world. You pay for it upfront, and if nobody reacts (because nobody is interested, or because the question is too complicated), you lost some money/reputation.