FORTUNE
To understand what makes NPS so compelling, it's necessary to know where it came from. The metric was introduced to the world in a 2003 article in the Harvard Business Review by Fred Reichheld, a Bain consultant. Rob Markey, who worked with Reichheld and now heads the firm's NPS practice, recalls, "I tried to tell my partners that we should use NPS as widely as possible to learn faster. We wanted more companies to use it and share their results. Those that were really serious would benefit from our consolidating the experience of all these companies."