"Where I believe the conundrum (that's a big fancy word like "mayonaise") would lie is who makes the determination and what are and what are the criteria? I mean just to be brought to the attention of the authorities? Pissed off neighbor/ SO/ coworker? How does the syatem where you are work?"

I'm not familiar with any details, but a pissed off neighbour is by far not enough to get a signed order. (Police won't even be bothered to show up, when receiving such a call.) And every order is subject to court evaluation. I think most people in NL don't even know such a thing exists. Most common use is when people are suffering from acute psychiatric disorders.

Example:
The husband of my father's sister suffered from severe manic episodes. He knew he could pose a threat to himself or his family during these episodes. So, the moment it started, my aunt calls the psychiatrist-on-duty, explains what is happening. They go to the hospital, psychiatrist evaluates him. If he deems it necessary, he advices for admittance. Order is signed. When he was calm enough and medication was adjusted, he was released.

Because guns are not allowed over here (and are not on sale at every corner), people wearing one will be arrested by the police without much ado. That makes a difference as well, I guess.