In The Alchemist by Coelho, why did Santiago have to experience the dangers of the tribal wars in order to reach the Pyramids?

In 's
story, , it is only because of the news of the tribal wars approaching that
Santiago sees the vision of the hawks fighting. When he speaks of what he has seen, the
alchemist comes to find out who is reading signs based upon the behavior of
his birds. It is here that Santiago and the alchemist meet, and the wisdom of Santiago's
responses based upon what he has learned on his long journey, impress the alchemist. They begin
their acquaintance. The two start out on a journey across the desert.

When
the alchemist and Santiago reach one of the warring tribes, they are...