Customer service
Complaints & angry customers: recover the order, keep the buyer
A complaint is a customer still willing to talk. Handle it fast and generously and a well-recovered complaint can leave them more loyal than if nothing had gone wrong.
An angry customer who complains hasn't left yet. They're giving you one chance to fix it. Handle it fast and generously and a recovered complaint can leave them more loyal than a customer who never had a problem (the service recovery paradox). Run a repeatable sequence: acknowledge fast, own it without over-apologizing, fix generously once, log the cause. Choose refund vs replace vs credit by what restores the relationship, and answer public negative reviews for the next reader, not the angry one.