There seems to be a lot of people who are a little misinformed when it comes to coverstock preparation, so I will try to clear up some of these.....
What is grit?
People often say I have the ball finished to a 800 grit ect. This is only half accurate. The surface of your ball is no where near 800 grit, otherwise it would feel like you where rubbing your hand over a piece of 800 grit sandpaper. Also, the proper way to sand a ball is called wet sanding, using water, or a water-soap as a medium between the ball and the abrasive used to sand the ball.
The water acts to "dull" the sandpaper, so as your 800 grit sandpaper actually acts as a higher grit number. Grit, simply is the a measurement used to determine the actual roughness or abrasivness of the sandpaper being used to resurface the ball....
What is a polish?
Polish is a super high grit abrasive. Sandpaper leaves tons of small scratches in a surface. The higher the grit sandpaper you finish your sanding with, the smaller the surface is under a microscope. Polish smoothes even the smallest scratches, leaving a smooth surface which then shines like a mirror. (Depending on how smooth you go.)
Usually I see people who say things like "the polish wore off.." Polish will never wear off, because there is nothing left behind after it is used. Polish simply smoothes the little scratches left from sanding. The polish may appear to rub off. In reality the haze that makes the polish appear to wipe off, is simply the wear and tear (and little scratches) the ball receives from normal use.
Polish is not a wax (and any polish contain silicon or wax additives should NEVER be used), so it doesn't wear out or rub off. The proper way to apply polish with a hand is through medium to high pressure, and a lot of rubbing the same spot. Not like waxing your car.
What is rubbing compound?
True rubbing compound is a rougher grit polish.
That is all for now, hope I helped, and I will be back later