Numbers in ledgers is a description of banking but money and banking are not the same thing.
Alternatively you could be describing money management, keeping a ledger of an account. Money management is the management of money but it is not money itself.
A collection of coins or bills is worth a certain amount and when you add or remove money the amount changes but you do not need to update any accounts.
There’s an actual limit to profit, they are called profit margins and different industries have different profit margins.