There’s a lot of data collected in marketing to help us understand what people do, and why. Not all of it is trustworthy. In fact, based on a mountain of research, it’s safe to say that the only data you can trust is data gathered by observing actual behavior. Data gathered by asking people what they do, what they think or why they behave in a certain way is notoriously inaccurate — and for a pretty simple reason. People always think there’s a “right” answer. Even when they answer questions on a personality profile, they tend to look for the answer that will present them in the most positive light. It’s why focus groups, in general, are a horrible way to make decisions — people have their own reasons for answering the way they do. So if you need to know how people will behave, don’t ask. Watch.