Share of Search: The New "One Number You Need to Know" for Media and Ad Effectiveness

The king is dead, long live the king. Twenty years ago, the Net Promoter Score (NPS) was introduced with great fanfare as "The One Number You Need to Grow." This article, published in Harvard Business Review by Bain’s Fred Reichheld. introduced the NPS. NPS was further popularized a few years later in Reichheld’s book, The Ultimate Question: Driving Good Profits and True Growth.The premise was that a single survey question that focused on customers’ willingness to recommend a product to someone else correlated directly with differences in growth rates among customers. Reichheld argued that willingness to advocate was "perhaps the strongest sign of customer loyalty."