I'm one of those that just vote pretty much when I see it sometimes i will wait a few minutes, I rarely see anything when it is fist out because I rarely look at the new tab. The only vote I don't like is the one I give on an old post 7 days old or more, have done that several times, and I do not understand how people can resteem things that are 2 months old, but glitches happen I guess. People voting for maximum profit are going to like you said, vote for maximum profit, and there really is nothing wrong with that.
3 minutes works, it is long enough to see if you want to vote or finish reading the post.