How did King failure to kill the Amalekites hurt David and his men?

Saul's failure to kill the Amalekites hurt David and his men because it led to a curse upon the land, causing a famine that lasted for three years and affected all of Israel. King David felt the effects of this curse when he was forced to flee from his kingdom to escape famine (2 Samuel 21:1). As a result, he and his men suffered in the desert, being separated from their homes, food, and other resources, making them vulnerable to various hardships and dangers.