Slower speeds have an outsized effect on safety. Consider that taking 20% off the velocity of the car takes 40% off the kinetic energy of the car, and between

Slower speeds have an outsized effect on safety. Consider that taking 20% off the velocity of the car takes 40% off the kinetic energy of the car, and between 20% and 40% off of the distance it takes for the car to come to a stop.