Why do people say that disc brakes are better?

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Disc brakes, also known as disc brakes, are named after their shape as the name suggests. The brake discs are made of alloy steel and fixed to the wheels, rotating with the wheels. Do you know the advantages and disadvantages of using disc brakes in most household cars nowadays?
Advantages of disc brakes
1. The braking torque is independent of the forward and backward movement of the car.
2. Good thermal stability. Due to the small size of the brake friction pads, their working surface area is only 12% to 6% of the brake disc area, resulting in good heat dissipation.
3. The thermal expansion of the brake disc will not cause a loss of brake pedal travel like the thermal expansion of the brake drum, which also simplifies the design of the automatic gap adjustment device.
4. Water stability is good. Due to the high unit pressure of the brake pad on the disc, it is easy to squeeze out water. At the same time, it is also easy to shake off water under the action of centrifugal force. In addition, the wiping effect of the pad on the disc, so after water is released, it only needs to be applied once or twice to restore normal braking efficiency, while drum brakes need to be applied more than ten times to restore normal braking efficiency.
5. Disc type friction pads are easier to replace and have a simpler structure compared to drum type friction pads after wear, making maintenance and repair easier.
6. The gap between the brake disc and the friction pad is small (0.05-0.15mm), which shortens the operating time of the oil cylinder piston and increases the possibility of increasing the force transmission ratio of the brake drive mechanism.
Disadvantages of disc brakes
1. The manufacturing requirements for brakes and brake pipelines are high, and the wear and tear of friction plates are high, resulting in high costs.
2. Due to the small area of the friction plate and the relatively small working surface of the friction, high braking hydraulic pressure is required, and vehicles with a power assist device are required to use it. Generally, servo devices are used.
3. The braking is quite rough. Two friction discs with friction lining surfaces can slide back and forth on the spline shaft, which is the rotating part of the brake. When braking, it can stop the vehicle in a very short time. In addition, the inclination angle of the ball groove on the pressure plate cannot be infinitely large, so the braking is not smooth.
Nowadays, disc brakes have been widely used in household cars, mostly for all wheels; A few are only used for front wheel braking, in conjunction with drum brakes on the rear wheels. Moreover, disc brakes are gradually being adopted in new and high-end models.