Why do Japanese cars not rust?

Japanese cars do rust, contrary to myth, but modern Japanese cars rust less than older Japanese cars from 1970s to 1990s because manufacturing and rust protection improved significantly. Older Japanese cars had reputation for rusting quickly due to thin steel and less rust proofing, especially in rust belt. Modern Japanese cars from Toyota, Honda, Mazda, Subaru use galvanized steel, better factory undercoating, cavity wax, improved paint processes, and better design that drains water, so they resist rust much better, similar to other modern cars. Japanese cars do not have special steel that never rusts, they rust if exposed to salt, moisture, and stone chips without protection, especially if paint damaged or underbody not cleaned. Reasons some people think Japanese cars do not rust include better quality control, use of galvanized and high strength steel, factory rust proofing improvements since 2000s, and owners often maintain well. Also many Japanese cars are assembled in North America with same rust protection standards as domestic cars. In dry climates, any car rusts less. So Japanese cars do rust, but modern ones rust less than old ones due to galvanized steel, better coatings, and improved manufacturing, not because they are immune, and regular washing and undercoating still helps prevent rust in salty areas.