What does a paper prototype reveal?
The paper prototype serves as a way of getting essential feedback from users so that you can tell whether you're on the right track. This is the first time in the user-centered design process that you'll take your ideas back to your audience to see whether you've got things right.
What is one benefit of a paper prototype?
They can be quickly modified, even during a session
Paper prototypes can be quickly modified in between sessions if it becomes evident something doesn't work. They can even be iterated on with the participant. This could lead to obtain more accurate insights from users.