"I didn't do anything"
That's the first and best defense every toddler learns. If you don't do anything, you don't get in trouble.
Somewhere along the way, it flips. "I didn't do anything when I had the chance," becomes a regret. The lost opportunity, the hand not extended, the skill not learned...
Wouldn't it be great if we knew what our regrets were when we still had time to do something about them?