warped rotors?

RGR that. for sure I can see that, so it would put pad on the rotor on say 1/3 of the surface (surface under the caliper at the light).

Or better yet, they do that and they are the creepers… screeching hault, hold on the break hard, creep forward a few inches, stop, creep, stop, creep, light goes green, creep, stop, car ahead moves a little so they gun it, and stop again. LOL Embedding pad all over that rotor unevenly.