I grew up in a farm with workers using several types if bladed implements. I mostly learned from them. Nobody taught me how to use a folder but it's really self evident that if you apply a lot of force in the wrong direction and the lock fails, you'll get injured. I was an adult by this time though and had been carrying a bali since I was in college. If I teach a child or an adult for that matter, avoiding injuries will be one of the first things I'll try to impart.
I grew up on various farms, myself.
Of course it could be that a lot of people get into knives when they're older and no one is around to teach them. But even then, by that time they should have sufficient (one would hope) common sense to know that locks are not infallible and can go bad if too much pressure in the wrong direction is applied.
Heck, even today, when I need to do any light stabbing with a knife, I don't just go at it trusting the lock, I'm careful. Even with a Cold Steel knife that I could put through a car door (I guess), I am still careful when cutting open my mail, or a box, or a plastic package. It's a sharp instrument lock or no, being careful just makes sense.