Rob Markey at Harvard Business Review – Transform Your Employees into Passionate Advocates:

“When frontline employees and managers hear directly from customers — when they see how customers scored their experience, when they hear what went right and wrong in the customer's own words — the effect is dramatic. Applause in the form of positive feedback inspires them to keep up the good work. Criticism often inspires employees to improve their performance on their own or to seek additional coaching so they can do better next time.”