Additionally, when a customer is upset with how you treated them, they are highly likely to tell a bunch of people about it. They are less likely to hype your product if satisfied. So one bad experience can undo a lit of good ones. These days, one person with a large social media following can tell a great many people for the same effort it would take to tell one person and may not stop until their ire has died down,…
I occasionally get some lazy high maintenance customers (B2B) that I’d rather not have. It gives me a fair amount of stress at times. Even though they generate revenue they are absolutely a liability and I’d pay to quietly get rid of them.
One lesson I've learned the hard way in business is: never be afraid to fire customers when they are costing you more than you're willing to pay. "Cost" here means monetary cost, sure, but also more intangible costs such as stress, aggravation, etc. Those a very real costs that may even adversely impact your product/service for your other customers.
Firing bad customers is good business practice.