Don’t be too sure.

I once saw an air duster can with a series of visual warnings.

The first showed that you shouldn’t spray the can into your eye.

The second showed that you shouldn’t spray the can into your ear.

The third showed that you shouldn’t spray the can into your ear with the can upside down.

Do you realize what that means? At some point, all of those warnings became necessary because somebody did them.

Furthermore, that means that at some point, somebody saw the “don’t spray the can into your ear” warning and though, “Well, it doesn’t show the can upside down…”