Heavy auditing – including from external auditors. There is far less lenience for digital currencies than physical currencies. You might physically miscount money, and so the issue would get addressed with the teller accordingly, but you can’t “add a couple of zeros”
But banks run on ledgers and so should always balance each other out. If cash into an account is $2000, cash out is $1000, and it’s showing as $1010 – this would flag as a $10 variance whereas variances are expected to be $0 – and so will **necessitate** an explanation.
Even simply saying “oopsie” will likely be followed by heavy discipline and a correction of the account. Evidence of intentional fraud would possibly result in a prison sentence. And all the evidence is recorded, traceable and often with little room for an “innocent” excuse.
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