Why is a car racetrack built with a steep inward slope?

So we want to know why is a car racetrack built with a steep inward slope. When a car is moving on a circular path, it experiences a centrifugal force. This force is bigger as the car speed rises. So to counteract that force the steep inward slope is creating a force component towards the center of the circle that comes from the car's own weight so the car doesn't slide off the road.