Lovation
Location, control and change of speed. A hitter has to have timing. A pitchers job is to disrupt that timing.
Yes and no.
Timing disruption won't work against good batters, especially when the game is on the line. Physically strong hitters who keep their hands back can hit the ball even if the timing is off. With modern bats, they can even hit them out of the park.
Against good batters, the pitcher actually has to make the batter believe the ball will end up at a different location.