Nulla poena sine lege, not in China or what?
wiki command economy. Just getting a letter is bad enough I suspect.
Think of how the mafia might signal to you to change behaviour, first they have a friendly tip and wave then maybe a word. If it ever got to letter you are into trouble fast. Do you really want to wait for an actual message to be sent in person before you finally do what you are told. How much power do you think the bank has to push back against the party in a communist system, you are a loyal servant to the state and to argue is disrespect to our dear leader.
You are free till you reach the end of your rope tether and then push too hard you may be hung with it
Or that is how I imagine it goes