Why do galvanized ironsheet do not rust Even thick zinc layer coated over the iron sheet is removed?

Galvanized iron sheets are coated with a layer of zinc, which protects the underlying iron from corrosion by acting as a barrier against moisture and oxygen. Even if the zinc layer is removed, the iron may still be less prone to rusting if it is passivated or treated with protective coatings or paints. However, if exposed to moisture and air without any protection, the iron will eventually rust. The presence of zinc also provides sacrificial protection, meaning it will corrode first, protecting the iron beneath it.