Ask people directly why they buy something, and you risk getting a distorted picture of reality. That’s why we identified the relative importance of 12 purchase drivers representing four dimensions of value for customers by surveying US and European survey respondents about a constant set of trade-offs between those drivers. A clear picture emerged: Reliability, features, and the lowest price are primary drivers, accounting for a large chunk of the purchase decision. But to differentiate from the competition, organizations must address secondary and situational drivers that their target customers care about. This report summarizes insights from our maximum difference (MaxDiff) analysis of why people buy.