Rotors are "wear" parts... they whole purpose of a rotor is provide a friction surface for the brake pads to scrape against to slow down the vehicle. In an ideal situation the brake rotor will last the life of the vehicle, and only brake pads will need to be replaced. But realistically you'll probably have to replace the brake rotors at least once or twice throughout the life of the vehicle.
If you want you can remove your wheel and spray paint the the surfaces on the rotor that don't make contact with the brake pads.