Richard Feynman wrote that "No matter who you are or how good your idea is. If there's no experiment to confirm your hypothesis, it means it's wrong."

The same applies to product development. It doesn't matter how beautiful they are or who wrote them: the user stories that make up our Product Backlog are just assumptions. And sometimes we discover that they are wrong simply once we give our product to customers.

We have an alternative: instead of planning a project (perhaps a long-term one), we can organize our product development experiment after experiment, continuously validating the assumptions behind the requirements (even before implementing them) and enabling true product agility.