Some countries (including the US) has a problem. Their numeric ID system was never meant to be as impactful as it is now. Nowadays, many companies in the US uses the Social Security number to provide for accounts, records, and a general means of identification. This number is also significantly powerful, especially in the realm of Social Security. There has to be a way to have a public number that everyone has, and everyone can know without it having a negative impact on the person’s life.
This is where the NIN comes in. The NIN is the Health1 number, the bank account number, ID card number, government benefits number, and the basis for their telephone number. In addition, those wishing privacy can acquire a private address where they will use their NIN number as the destination for postal mail. The number can be freely given to anyone for any reason. With that said, the NIN is fine with having it public. Now some people may question the rationale of making it a bank account number, but the banking system is designed that the sender sends money to the recipient, and the recipient can not take money from the sender. For everyone but the account owner, the account number is for deposits only. If the owner wishes to send money to the recipient, they will just need to know the NIN, and send it off. This is vastly different from many banking systems.