It’s because you can’t bounce a ball on the bottom of a pool.
One of the best survival techniques while bound in a pool is to bounce off the bottom.
Get air, exhale.. descend.. bounce.. lather rinse repeat.
Its hard to hold a basketball under water.
You’ll Bob to the top.
It’s funny, we used to try to stay down with the ball.
Then I remember us making a diving helmet with an old pickle crock.
We cut a section out and inserted plexiglass, then we drilled a hole for the bicycle pump...
It didn’t work LoL the crock kept floating off!!