Fingers: If the width of a human finger is 2.2 cm (7â8 in), then a million fingers lined up would cover a distance of 22 km (14 mi). If a person walks at a speed of 4 km/h (2.5 mph), it would take them approximately five and a half hours to reach the end of the fingers.
The rotors on a vehicle can last anywhere from 30,000 to 70,000 miles and sometimes more. A licensed mechanic, such as one from YourMechanic, can evaluate the rotors and advise you on their status; they may not need to be changed as often as the brake pads. Like brake pads, they should be replaced in pairs.
I've made brakes last more than 90,000 miles on my personal vehicle and, as a racecar driver in 24-hour events, kept brakes alive for hours. In other races, I burned the pads almost down to the backing plate in fewer than 50 miles. That was perfect. The events were but 40 miles long.