When many hundreds or thousands of transactions are being done each day, and whenever there is human input involved, error accounts are necessary to keep the audit trail intact.
Error accounts also play a role in improving customer service.
GAAP recommends daily or weekly monitoring of error accounts depending on volume and transaction size.
It is typically up to the company or applicable government department's accounting department to monitor the error accounts that it has in place.
In 1994, Nick Leeson used a poorly monitored error account at Barings Bank in an attempt to cover up evidence of his trading losses and place ever larger unauthorized trades to win back the money.