Originally Posted by Meeni
If you change pad compound, you have to hone the rotors to remove the previous pad type bonding material (otherwise, break-in cannot happen, and different compound result in unpredictable results and braking performance). If you keep using the same pads, and the rotors don't have pronounced grooves, it's ok to skip resurfacing.
Resurfacing a rotor cost money, removes life from the rotor, and may very well cost more "per miles of remaining life" than outright changing the rotor. Most people have to change rotors the first time on their own dime around 70k, at which point the rotors are done, or so close that it makes no sense to pay the cost of resurfacing for so little use left in them.
Well, true, but a little fine grit / garnet paper'll take old pad material off.