Have you ever had mechanical issues but been embarrassed for the mechanic to actually take a look at the hot mess that is your engine? Having a car that is shiny on the outside does not mean that it is going to be that way on the inside. If you don’t get the engine detailing once in a while you could have the car equivalent of a good-looking person who has just a terrible personality. Like any person, your car’s interior is far more important than its exterior aesthetics. Every vehicle, its overall worth and its effectiveness comes down to what you have below the hood.