In some cases, you feel comfortable with a certain speed (rpm), and feel that this works best with a certain product. However, not all your pads are the same size and you want to know what speed setting you need to maintain the same speed.
Different jobs require a different speed setting on your polish machine. Although they can differ slightly per machine, the settings are fairly general per action. Knowing the right speed setting can make the difference between half results, and proper results.