Question

What were the qualities of Narcissus that led to his downfall ?

Answer 1

He was too engrossed in himself. Actually it depends on various things. There areany versions of his story. Let's take Ovid's version.
He wasted away because he could not touch and feel his own reflection in a river. He also was ride to all people who fell in love with him, which caused the goddess Nemesis to curse him. Echo, the nymph, prayed that Narcissus get cursed.
Hope this helps.

Answer 2

sorry,I don't know the answer of his question.