never too old

Or too experienced to do something stupid.

Like, you're watching a drill rig do its thing and it's a beautiful day and you idly notice a little piece of something or other fall on the ground, so you mosey over. It's a strange piece of metal. You pick it up...

and get a high 2nd degree burn on your fingers because what you tried to grab was actually a tortured, red-hot chunk of the engine that had just been spat out of the exhaust.