Brake Loud Noise problems of the 2010 Hyundai Elantra

Tl-the contact owns a 2010 Hyundai Elantra. The contact stated that while driving 5 mph, the vehicle made a loud noise as if something was being dragged under the vehicle. Upon stopping, the contact looked under the vehicle and there was nothing on the ground. The vehicle was taken to a dealer where it was diagnosed that the rotors were rusted, grooved and pitted. The vehicle was repaired. The manufacturer was notified of the failure. The failure mileage was 12,044.