Inc. PremiumInnovate How to make the most of what you put in your customer health index. BY SYDNEY SLADOVNIK, EDITORIAL ASSISTANT @SYDNEYSLADOVNIK Feb 6, 2026 Photo illustration: Inc. Art; Unsplash (2) Listen to this ArticleMore info 0:00 / 0:00 If you were a merchant in ancient Greece—or at least before the dawn of the internet—you had a fairly easy way of knowing how well your business was doing. Do your customers keep coming back? Are your sales higher than your expenses?