What does the greater the speed, the greater the braking force needed to stop the car mean?

The greater the speed, the greater the braking force needed to stop the car. This means if a driver is travelling at high speeds and needs to brake, they need to apply a very large braking force. A large braking force will cause the car to decelerate rapidly. But it will also cause a large amount of kinetic energy to be transferred to thermal energy in the breaks. This can cause the brakes to overheat and cause the driver to lose control of the vehicle.