When I was a hot-headed 20-something, I returned a rental car to one of the national agencies. Dissatisfied about something, I stormed into the airport rental office, furiously paced in front of the desk, and loudly lambasted the agent. The next time I tried to rent a car from the company, no one would let me. It was several months before I found out I had been blacklisted, and for at least a year I could not rent from that company. I had been fired.

Customers can be fired for different reasons. Employees may feel threatened or abused by the customer, as in my case above. Or the customer may simply be unprofitable. Whatever the immediate reason, firing a customer indicates that someone in authority in the company perceives the customer to have zero or negative value to the company. Put another way, the tangible and intangible costs of serving the customer outweigh the cash and any goodwill received from the customer.