It's easy to think about corrosion if you're doing work on the seashore, or in a battery plant, or even in a plating shop. Yet, you often have such problems in the most mundane locations.
One, common around here, is our alkali soil. The common "Bell" box that we use outdoors is absolutely unsuited for direct contact with earth.
First, because - gasket notwithstanding - they invariable get filled with dirt and roots. Second, corrosion.
Here's a fairly recent install:
This was done, even though, just a few yards away, was this box:
There's simply nothing left of the box. True, the plant matter from the bush probably didn't help ....