Back at a previous job in a Japanese Traditional Company over a decade ago, a guy had been trying to quit for months.
‘Tradition’ has it that before you quit, you have to schedule a chat with your team lead, who will then direct your request to the department head for approval. (Yes, you need _permission_ to quit. Fuck the law)
This person was a fairly senior engineer and thus quite essential to the company so they kept giving him the run around, rescheduling his chats and not giving him a direct answer.
One day, a letter addressed to the dept head came, looking all important and official, like it came from a client. The dept head opened the letter and after taking a quick glance immediately tossed it. Our senpai engineer then jumped up and shouted across the entire office, you have seen my notice now, you cannot deny my resignation! I quit! And he stormed off like a boss.
Basically the gist of the story is that they cannot deny your resignation if requested but as long as they don’t acknowledge it they can pretend you never requested it. That’s the origin story of these companies.