I am with leftyinhawaii - you only need a true resurfacing if you do not care much for your ball in daily life. If you clean a ball frequently and avoid oil absorption, some slight surface refreshments to keep it at the desired finish are enough. An oil extraction every now and then is also not a bad thing, and more effective than resurfacing to bring back performance.
This said, judging if it was time to do something baout the surface is when you feel that the ball has lost some bite, or visibly tracked out.
When resurfacing, a good amount of the coverstock is sanded away at low grit. Therefore, the ball becomes smaller and after some time even illegal! Scratches and gauges might disappear, but as long as these do not hamper the ball's traction, I'd rather "keep" them and store surface material through a mere surface refreshment.
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DizzyFugu - Reporting from Germany
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