Why did the hyenas kill scar?

Scar was killed by the hyenas in Disney's "The Lion King" because he failed to maintain their loyalty and trust after seizing power. When he led them to believe they would share in the spoils of his rule, he ultimately betrayed them by attempting to take all the glory for himself, particularly in the battle against Simba. In the end, the hyenas turned on Scar, realizing he had used them and was no longer useful to their own ambitions.