f u-nolic tip?

[Patrick Johnson]

All balls wear down over time, just from colliding with other balls

I think that's a factor, but the cloth can be a larger factor if it is not cleaned well. Chalk is ground up sand. Chalk in the cloth turns the cloth into sandpaper.

And for the cue ball, being hit every shot with the chalked cue tip may be the biggest factor.

pj
chgo

 

[Flintlock]

I thought this guy was writing a poem at first.

 

[Bob Jewett]

And for the cue ball, being hit every shot with the chalked cue tip may be the biggest factor....

And the worst of those contacts are miscues -- the tip scrapes across the ball.