Thread: Rust - What am I doing wrong?

Could it possibly be condensation?
If the metal is colder than the air around any water vapour will condense on the surface, damp rid or not. It would be particularly apparent when the inside of a safe located in a garage is chilled from overnight low temperatures and opened to warmer ambient air say later in the morning when things warm up a bit.
I would have thought Inox would be up to the challenge as it is excellent stuff. Maybe an anomaly with the finishing?

Maybe try a light bulb or other heat source, personally I use Inox for everything with no complaints and run a lead lamp in the safe.