Why dont the angel of the north need painting?

The Angel of the North, a massive steel sculpture in Gateshead, England, is designed to withstand the elements without needing a paint job. Its weathered steel surface, made of Cor-ten steel, develops a protective rust layer that prevents further corrosion. This natural weathering enhances its aesthetic and ensures minimal maintenance over time. Additionally, the artist intended for it to blend with the landscape, making frequent painting unnecessary.