Shooting this way doesn't give the ball much of a chance to get up in the air. Better shooters employ their legs and entire bodies to shoot with. They don't just jump to get elevated or to initiate the shot. They are shooting FROM this energy. Also, note that the more your shot comes from the lower body, the more the upper body can relax, quiet down and become constant and predictable.
Shooting starts to become effortless.
If you wait before you shoot, the percentage drops accordingly. There is a direct correlation. But don't just believe or disbelieve me. Check it out for yourselves. Using more leg and lower body power gives the shot the stability like that of a rocket taking off.