Normal Wear and Tear
Things wear out. Many of those things can cause overheats if they break. As we've seen, even one overheat can severely damage a car. Many of the components that can cause overheat when they wear out are cheap. They should be replaced in a preventive maintenance program:
Belts
Hoses
Hose clamps
Thermostat
Radiator cap
Coolant
By replacing these cheap and easy components on a regular schedule of preventive maintenance, you limit the likelihood of damaging expensive parts such as the radiator, water pump, head gasket, heads, or engine.