Many people reach a point in their life where they run through a list of things they've learned. It rarely happens when you're young, you're too busy just doing things to think about whether reminiscing has some sort of learning power. It doesn't necessarily happen when you reach the "Been there, done that" stage. Even articulating that maxim just indicates an experience — good or mediocre — something akin to a photo often made as an one-up to a suggestion or a smartass remark to someone else's remembrance.
Interesting conclusions. Although a couple sent me to the dictionary (Google), I think I agreed with most, especially the last one.