Why Is A Manhole Cover Round And Not Square

Riddle: Why is a manhole cover round and not square? Can you guess the two reasons?

Answer: 1: It can't fall through the hole like a square one could. 2: It can easily be moved by rolling.

Source: https://www.riddles.com/index.php/822

Why is a manhole cover round and not square? Can you guess the two reasons? — Why is a manhole cover round and not square by Anonymous v1.

Riddle: Why is a manhole cover round and not square? Can you guess the two reasons? Answer: 1: It can't fall through the hole like a square one could. 2: It can easily be moved by rolling. — by Anonymous v2.