The training mentioned above exists for a reason.
And that training has been done, and done, and done, and done unless someone is a genuine newbie.
The problem lies in two things, one said by
@thecomputerguy , " no one on the end user side will read it or give a damn," (or pay attention during live training, either), and one you brought up, lack of policy that must be followed.
I stand, adamantly, by my statement that this is the result of a combination of complete carelessness and willful ignorance, not lack of exposure to what needs to be done.
THIS IS NOT NEWS. IT CANNOT BE TREATED AS NEWS. DOING SO HAS HAD NO EFFECT FOR DECADES.
Your suggestion about policy, and enforcing it with swift and severe consequence, is about the only thing that can be done. And, sadly, even if it works within an organization it's one time too many after the fact. There is just NO excuse for these kinds of "accidents" today. Period. End of sentence. (And to be clear, I'm talking about business settings with professional and long-term support staff. None of them should be unaware.)
I've decided that, as a class, residential users are a lost cause. There are some, and I have a number of clients, who do listen and adjust, but there are others who simply persist in whistling past the proverbial graveyard as though that should protect them. Blissful willful ignorance, and willful ignorance has no cure except, possibly, getting burned once. Even that doesn't work in many cases.