The higher your elbow on your shot form, the more likely your shot will go in. Think about it for a minute. Put yourself in the perspective of the basketball. As you go flying in the air and come down, the higher you are, the bigger the hoop is. The higher the ball goes, the larger the area is that the ball will go in.
If someone shoots with low arc, the area is limited to where the ball can go. The smaller the area the ball can go in, the lowered the percentage that the ball will go in there. To get your arc higher on your shot, then get your elbow on your follow through above your head. The flatter your arm on follow through, then the flatter your arc will be.
Don't do this:
Instead, do this: