Recently, I was returning home from two farm visits at which I discovered that both farms had been dutifully replacing their rubber teat cup liners every twelve months, just as they had done for many years.
While I was contemplating liner change intervals in the car, I passed a car on the side of the road accompanied by a police car with lights flashing.
Because the traffic was slow, I observed the driver and the policeman having what appeared to be an animated discussion whilst pointing to what were obviously very bald tyres on the car.