Philippines

The main reason to chalk a pool cue is to increase friction between the tip of the cue and the polished surface of the cue ball.

There is no flat surface on a cue ball. And your cue tip, whether made of out leather or rubber, is very firm and will not conform to the round surface when making contact.

Without the added friction, your cue tip will slip right off the spherical surface of the cue ball, resulting in a miscue and subsequent embarrassment.