I don't wash my car at all. Automotive paint is tough stuff - decorative, sure, but it's there to protect the metal. I have a friend who layers on the "protective" products, wax sealers, etc. At what point is it silly? It rains sometimes where I live - that takes the pollen and road dirt off. My current ride is 10 years old and I've never washed it, except the wheels once, I think. The paint is fine. . .and life is short. If you enjoy the chore, go for ir, sure - but I think it's probaly a waste of time otherwise, and I doubt it adds longevity to a vehicle, unless it's an antique or much older machine.