The deluxe-model upsell trick: Don't you want the best? Don't you want to protect your family? Galvanized springs may be offered to you at extra expense as "longer lasting". Although bare springs (also called "oil tempered") can develop a light film of rust, the eventual failure is due to fatigue and not corrosion. The use of coated springs (whether galvanized, painted, powder-coated, or surface-converted) is mostly about appearance: the customer likes his new door to look shiny, and the customer doesn't like repair parts that show superficial rust from storage.