To improve, it's important to do footwork drills. Some are simple, such as side-to-side forehand-forehand drills. Others are more complicated. For example, you might do a drill that starts with your partner pushing to your backhand, you backhand (or forehand) loop to his backhand, and then he blocks to your forehand.
Advanced players understand that in these rote drills, they are practicing only the footwork and the stroke. But many beginning and intermediate players don't get that, and try to play it like it was a match. After that first opening shot, they know the next ball is going to the wide forehand - but because they would not know this in a match, they wait until the opponent does the shot, and then move. That would be fine in a random drill, where you don't know where your partner is hitting the ball, but not in the rote drill described here. And so what happens is you end up knowing where the next balls going - to the forehand - but do not immediately move there. Result? You are practicing hesitation!
So remember that if you are doing a rote drill, don't hesitate to move immediately to where the next ball is going - you are practicing footwork and strokes, and don't want to make hesitating a habit. When you want to practice reacting to where your partner is hitting to, do a random drill for that, where you don't know where he's going, and so have to truly react.