Though “Do as I say; not as I do” is a Bad Idea generally, if someone is experienced with a tool or process and is over 18, you may see them taking shortcuts that are potentially hazardous. This is still a Bad Idea generally, though experience can substitute for safety devices. But that experience has to be there; if you just got your Learner’s Permit, you would probably not be able to safely drive to San Francisco, which any experienced driver could do. And if you’re under 18, you MUST use ALL relevant safety devices, experience or no.