The users are the ultimate judges of your product, but predicting their behavior in advance is really hard. Even if you ask your users what they want, it is not guaranteed that what they say is what they really need. There are many examples of organizations that have made product decisions by interpreting their users input literally, leading them to unsuccessful results. For example, Coca-Cola adjusting the flavor of the new Coke based on thousands of sip tests and Walmart spending millions in reorganizing their aisles are just two of the most well-known examples.

As research shows, people are affected by the introspection illusion, a cognitive bias that limits our capabilities to explain our own behavior and predict our future attitudes.

In order to deeply understand how your ideas work in practice, you need to observe how people actually use them. You need to focus on the reactions of your users, not their opinions.

You would want to get quality feedback from your users as early as possible. The sooner you check how well your solution works for your users, the better. Learning from your users as you design your product allows you to make course corrections when necessary, reducing the risks of moving too far in the wrong direction.

Testing your ideas with users is a key step in the design process. In this chapter, we'll describe a testing approach to get useful feedback early in the process. By recreating realistic-enough scenarios, you can test your ideas before you start building your product.

Observing your users with your product in their hands is a powerful learning tool. However, in order to get quality feedback that helps improve your designs, you will need to organize the testing process appropriately. This requires you to understand the purpose of the testing process, plan the testing steps to avoid any interference, and learn how to observe your user's behavior in order to extract relevant conclusions.