So, you read something you like, and you want to vote for it. But it only took you anywhere between a second, for a short post, to 29 minutes (for example) to read something and decide. Now you have to wait anywhere between 1 to 30 minutes to maximize your curation reward potential. And of course, think about other people voting before the 30 minute mark.
Who wants to wait even 1 minute from the time they decide to vote, to the time they cast it? It just doesn't make sense.