was it by any chance on a chrysler or ford? because in my experience of brakes, chryslers and fords rotors glaze very easily. and this is probably what youve got, and if its a chrysler, the newer ones not brand new but newer models had brake pads without the chamfer on the edges and if they did, they were minimal, so they didnt dissapate heat very well, that, combined with non vented rotors, and every chrysler was coming in with glazed pads and rotors.