How do you inspect canned food after hot or humid storage?

Something I have been trying to get clearer on is how people inspect canned food after it has been stored through a hot or humid season.
I know obvious things like bulging, leaking, or badly damaged seams are a clear reason not to keep a can. But what do you do with cans that only have a little surface rust, a small scratch, or some staining on the outside?
Do you rotate those out first, clean and inspect them more closely, or discard them right away?
I am also curious whether people have found humidity, temperature swings, or storing cases directly on concrete to be the biggest problem over time.