Why do transport trucks sometimes have many spare tires hanging from their undercarriage, almost as many tires as those being used? Surely they don’t expect almost all tired being used to break down at once?

Question

Why do transport trucks sometimes have many spare tires hanging from their undercarriage, almost as many tires as those being used? Surely they don’t expect almost all tired being used to break down at once?

In: Engineering

Answer 1

Imagine you are going to a party, do you bring 4 napkins because there are only 4 people attending? Or do you bring a whole pack incase something happens?