We cannot account for every possibility. With the added human element, that we are dealing with people having a complex set of wants, needs, and emotions not to mention the stresses that may be on their shoulders, if you are in business long enough, things will go wrong.
Negative reviews are inevitable.
It’s one thing to work to prevent them (and you should), but you need to be prepared for if (when) you receive one.
Will that negative review damage your brand’s reputation or merely be a minor negative footnote?
For the past 20+ years I have seen and worked with small business owners who still try. They develop and implement customer service policies to cover everything they see which could possibly go wrong. They continually train and work with employees to the nth degree on how to handle customers to eliminate the situation from arising.
The concern is that it creates a false sense of security.
If you fail to prepare to handle a negative review thinking you will not receive one, what happens when you do?