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I just tried to award a bounty to an existing answer. Now when I click the +50 it says I need to wait 23 hours?
What's the point in having a waiting period to award an existing answer to someone else's question?
Authoritative reference needed Looking for an answer drawing from credible and/or official sources.
Canonical answer required The question is widely applicable to a large audience. A detailed canonical answer is required to address all the concerns.
Current answers are outdated The current answer(s) are out-of-date and require revision given recent changes.
Draw attention This question has not received enough attention.
Improve details The current answers do not contain enough detail.
Reward existing answer One or more of the answers is exemplary and worthy of an additional bounty.
All except the last one are used to get more informatio in my opinion. The last one seems like it should be an instant reward.