[sp332]

Lots of people with impressive accomplishments don't have self-esteem. Impostor Syndrome, Dunning-Kruger etc. If you don't have self-esteem, you'll let yourself get pushed around because you think you're not really worth anything. But with it, you'll start to see your own potential, which is a good motivator to start working toward it.

[rustynails]

Self esteem is a double edged sword as it does not consider empathy and may lead to narcissistic values. That's the flaw with the self only aspect.