Is the Net Promoter Score a reliable performance measure?

Customer satisfaction and customer loyalty have become very important concepts in modern management and quality models. A number of measurement frameworks have been proposed, and especially the American Customer Satisfaction Index and its European counterpart, EPSI Rating, have been accepted as good solutions. In 2003, however, Reichheld published an article in HBR, in which he claims that the Net Promoter Score (introduced by himself), is the only number you need to grow, and the only number you need to manage customer loyalty. We claim that the NPS is an inefficient and unreliable measure of customer loyalty and this paper clearly demonstrate that the NPS is by far inferior to the standard measures of loyalty used by the ACSI and EPSI Rating.