Today I used the Porter Cable polisher for the first time. Picked it up at a DeWalt store for 99$ (it's a refurbished unit).
Used it to apply wax on a Honda HRV. So first thought: That thing seriously lack power

Had to put it on speed 6 to have any spinning of the pad worth mentioning, even without applying any pressure (just waxing the car with D166).
So halfway through the process, I go to the pad washer to remove some residue the pad had picked up and the white buff&shine foam pad desintegrated when I lifted it up from the grit guard to dry it off. The velcro was completelly torn off the backing plate. Never seen anything llike that in 6 years doing this profesionnally. So I put my hand on the backplate and it's boiling hot. Very strange indeed!
So depending on what machine you are using, Changing pad often might be a good idea. On my Rupes 21, I usually switch pad once halfway through the process. I clean the pad after every panel if I am doing any type of correction, and when needed if applying wax. Using 13 pads per vehicles seems like overkill to me, but if that is what you want to do, more power to you

I would not mind doing that if I did not have to clean all those pads afterwards, that's a good hour of pad cleaning to do that many.