All it needs is one person to press a wrong button and a computer could be issuing a newspaper delivery free forever.
Regularly we get clients from other systems and while our data entry people are retyping the information into our system, they find mistakes. They have a rule of the thumb that states for every 200 home delivery accounts, they expect to find an average of one (1) mistake. So if you are doing four hundred home deliveries a week, they expect to find 2 errors.
The expected yearly cost to the newsagency say servicing 400 home delivery clients = (2 errors) x (weekly home delivery paper charges x 75% + delivery costs) x (52 weeks a year)
It may pay you to do an audit of your accounts now!