Why didn't Achilles want to fight again?

Achilles initially refused to fight again due to his deep sense of betrayal and anger over Agamemnon's decision to take Briseis, his war prize. This humiliation led him to withdraw from the battle, prioritizing his honor over the collective Greek effort. Additionally, Achilles grAppled with the realization of his mortality and the futility of war, which further fueled his reluctance to re-engage in the conflict. Ultimately, it was only the death of his close friend Patroclus that reignited his desire for vengeance and compelled him to return to battle.