I suspect we are coming at the same thing from different angles.
You can’t have a culture that tolerates accidents like this, so get some systems in place to prevent them. It’s not about one person or piece of equipment. Swiss cheese model etc.
You said something quite different sounding than here. Here you mention systems to prevent mistakes. Your original post said
you aren’t allowed to make mistakes of this magnitude. It really is that simple.
That does not mention prevention systems and instead put the blame squarely on the person making the mistake. They "simply should not have made the mistake, duh!"
Someone has allowed some crap systems to exist by the time something like this happens.
You’re right that my initial post makes it sound like I blame one person, and I do. However it isn’t just the person who didn’t close the hatch. I blame the whole command structure and particularly those at the top of it.
