You can upvote any number of posts though, its just your voting power will decrease. So if you post 11 posts a day and upvote each at 100% then you will regenerate all of your VP by the next day and you will have earned the maximum potential from your own rewards.
The only time the reward goes to someone else is if they upvote someone else which is the entire point of the PoB algorithm that steem works on, it is supposed to be the communities decision on how much a post gets rewarded... not your own decision. No one person should have say over the rewards of a post