The correct answer to this open question is the following.
Myths provide life with meaning because people believe that part of what is said in the myth is true. This belief became part of the people's history, culture and tradition to the degree that the "myth comes to life" with the passing of the story, the way people identify with it to the degree that people refer to it as part of their identity.
Let's set the example of Robin Hood. He is a myth, but is part of the culture and tradition of many people in England, to the belief that they think he existed and truly helped the poor.