Voting accurately refers to: The earlier you vote on a post, that becomes popular later, with many votes, the more you earn. For example, if you were the first to vote on a post but no one else ever voted on it, you might earn $0.10, whereas if you voted first on a post that many people voted on afterwards driving the price up, you might earn $10. Because you are limited in voting power to roughly 20 - 40 votes per day, the "accuracy" refers to picking the best ones.

So you will always make a small amount for voting --this is the benefit of having Steem Power--, but in order to maximize your earnings into a larger amount, you will have to find good/popular content earlier than others do.

This is all contingent on the amount of Steem Power you have of course. If you have very little Steem Power, trying to earn from voting is mostly a waste of time.

Hope that helps. : )