Rules prevent cheating, which would ruin the game.
Click on the 'NBA Rules' link on this page to see the rules and regulations of the National Basketball Association.
23 are allowed
More height, speed, strength, athleticism, skill among the boys
They enforce the rules of the game - in the same way a football referee or cricket umpire enforces the rules !
It was important to implement specific rules for basketball in order for the game to be fair. The rules make the game universal no matter where the team is from. Also, they make it easier for players to understand what is expected of them.
The added backboards, rims, rules and many more.