Any time you struggle with a bad habit, addiction, or compulsion you don’t have under control.

Any time there’s a skill discrepancy that enables one to do things in a more dangerous but more convenient or effective fashion and where someone else is yet to acquire that level of skill.

That’s not uncommon in trades - plumbing, construction, auto mechanics and the like.

There are tricks and techniques that one can learn over time to make things easier or more efficient, but they’re often complex enough or require enough skill and experience that if you don’t know what you’re doing, you’re just going to unnecessarily screw things up trying. So new people are taught the standard, safe, dependable way of doing things, even if that’s not the way the old hands do it.

Edit to add: in a moral context rather than a practical one, I don’t think it ever is appropriate. IMO, the first requirement for any moral stance is that one abide by it oneself, and unless and until one has managed to accomplish that most basic of tasks, one has no standing by which to even meaningfully comment on other people’s behavior.

It’s technically appropriate anywhere where the teacher who knows how to do something has lost the capability to do it and instead is giving the knowledge to someone who still has the capability.

When driving a car. Don’t want the passenger grabbing the wheel!