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It does, but i think that doesn't matter, in this case I'm referring to the hat as a "reward" only in the sense of a badge. It might not be important in itself to a user personally, but it does is a metric that influences interactions for it boosts confidence. Losing it day by day ends up defeating its purpose because it motivates blind zapping just to keep it, thus not being any more a good metric of user activity nor a good way to motivate good content compensation
that doesn't make sense, you have 24 hours to zap and thousands of posts/comments, how does that encourage random zaps?
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You are saying it: you have 24hrs, hence, a day. That implies daily commitment. Just one day off and it's all gone. Expecting a user to not to miss a single day to keep score, as another user posted above, ends up causing anxiety. You have to devote time, and even more, mental energy, to consciously zap something you consider worthy. Most probably, you wont have that time and energy strictly every single day, so to not to lose score and rewards, you just enter quickly, zap blindly, and done.