Why is stitching on a baseball important?

Answer 1

There are 108 double stiches in an official Baseball. They are carefully stiched in a pattern that goes from wide to narrow because this effects aerodynamics. When the air passes over the ball the stiches help produce a more streamlined effect which reduces the amount of drag on the ball-Drag is the reistance an object faces when it collides with air molecules, it is a type of friction which can slow down the ball.

Answer 2

It gives you better grip and the stitches create wind resistance causing the ball to move in different directions (different pitches)