The ball is yellow for high visibility, quick reactions and speed which means better performance.
High visibility reduces the risk of injury from a flying weighted ball.
An easily recognized colored stripe around the center identifies the ball weight. The ridges and roughed up texture are for grip. They act like the seams on a baseball for throwing. The ball is soft, user friendly, so a rebound can be easily caught and thrown again. It will not bounce back at you like a hard, weighted basketball.