Final answer:
Coelho keeps Santiago in Tangier for a year to test his perseverance and commitment to his personal legend. By staying in Tangier for a year, Santiago learns valuable lessons and gains the necessary experiences that ultimately prepare him for his ultimate destination.
Step-by-step explanation:
Coelho's purpose for keeping Santiago in Tangier for a year is to test his perseverance and commitment to following his personal legend.
Tangier represents a place of temptation and distractions, where Santiago must overcome challenges and stay focused on his journey towards fulfilling his dreams.
By staying in Tangier for a year, Santiago learns valuable lessons and gains the necessary experiences that ultimately prepare him for his ultimate destination.