Having a bounty open, it's almost five days, but I haven't got any answer. But being said that "All bounties are paid for up front and non-refundable under any circumstances.", neither I am going to get an answer not the bounties back.  Though I have read somewhere in comments, that if there is no risk, everyone would have stared bounties. But isn't it unfair not to get those bounties back for those where there haven't been posted any answers or where none of the answers meets the eligibility criteria? Though you can have bounties disabled for such questions to be started again.   I could have considered deleting the question before starting bounty, but I neither got any comment nor any downvote to indicate if there is a problem with the question.  PS: Had I been Jon Skeet, loosing a thousand bounties wouldn't have mattered :)
I have  with a bounty that will expire in a few days. It looks like nobody will get the bounty; only one answer was posted during the bounty period, and it has no upvotes.  In cases like this, the bounty is thrown away.  Why isn't it refunded instead, if no answerer has earned it?
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The premise was a bureaucracy whose job it was to manipulate events in human history by making the smallest possible change that would effect the desired outcome. Not time cops in the sense of going after law breakers.  The intent was to maintain a policy of non-interference as much as possible but when interference was warranted then to make the least possible change and to do so invisibly.  For example, they might take someone's keys off the dresser and put them just out of sight underneath the dresser where they plausibly might have fallen.  The subject would never know of the manipulation but would then be delayed getting out of the house and the ripples grew from there to avert a war or otherwise affect events on a large scale.  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