AIBU to think violently rattling an occupied toilet door at work is rude?

It’s not always clear whether it is occupied or not.

Fair enough; but you surely go to open the door normally, and if it doesn't open, you know that one is occupied and look for a vacant one or wait?

Toilet door locks aren't designed to be like bank vaults; most people could force them open and gain access to the occupant/facility for whatever reason if they desperately wanted to (indeed, this is a crucial feature in case somebody inside needs emergency assistance); but they work on a socially-understood basis, whereby they give the very clear message to any normal, respectable person who gently tries the door that this cubicle is currently not available.

Rude. I would say something. Did u feel vulnerable in case it was a man?

Most standard cubicle doors don't actually close fully on their own, so if you see that a door is fully closed, the likelihood is that somebody is in there. I would always push a closed door very gently and slowly, in case the lock is broken, or there's somebody in there who forgot or struggled to lock it - children are very good at forgetting to lock (or are maybe scared to in case it's stiff and they can't unlock it again).

I appreciate it's different if the single toilet is a self-enclosed room with a proper door in itself; but again, if you try a toilet door and it doesn't open, your parents did a shockingly bad job if you can't work out why that's probably the case.

I think there are a lot of people out there who really cannot think anywhere beyond their own needs and wishes - the so-called 'main character syndrome' - where they cannot fathom that somebody else may be in there and they will have to wait or find another one. Even if they're thinking "But I really need the toilet!"... erm, yes, as does the person who is currently using it!

Well again, if you know there's a chance someone is already occupying that cubicle, why approach the situation assertively? Why not have some consideration for the person who may already be in there?

I can't believe that a thread is necessary on the bare fundamentals of decent manners and what you don't do when someone is already in a bog cubicle. But here we are. A detailed division over the simple social contract of basic courtesy.

Cede over women's once-protected spaces and unfortunately this is the likely outcome. No question that women can be equally as rude, but intimidatingly predatory behaviour is overwhelmingly in the male domain.

Maybe the constant whingers that society is going down the shitter actually have a point.

Just assertively trying to get into an engaged toilet that was in use. Sure bro...

I'd certainly ask them WTF they think they're doing and tell them to pack it in!