[Steeveedee]

Disc brakes use the pads to continuously wipe the rotor so that there is less likelihood for poor performance when it's wet out. Also, they clamp the rotor as opposed to pushing outwards on a drum. In the case of thermal expansion of the rotor, braking performance is not diminished. In the case of drums, the thermal expansion of the drums causes more pedal travel as the drums heat up. Disc brakes are also self-adjusting.

Let me just ask the question- Since drum brakes are cheaper, why are all manufacturers required to supply front disc brakes? They cost more. Disc brakes are on there for performance reasons. This is a "tastes great, less filling" argument that you will see all over the internet, and the fact is that front disc brakes have more, and safer, stopping power.