Someone lacking clarity as to what is truly important can still feel inferior, based on nonsense that has no bearing on self-worth.
An example is Nebechudnezzer, who was a monarch with tremendous power, but nevertheless failed to find satisfaction. The Midrash says he constantly felt embarrassed because he was short and fat.
He had a choice of focusing on his power and enjoying it, but instead focused on his physical shortcomings. He thus turned his life into a constant state of misery - when he should have rather ignored these things (which pragmatically made no difference anyway).
As a tool, ask yourself: "How does a certain factor prove that I am less of a person?"
Remember: Lack of skills and talents are practical liabilities, but in no way detract from the essential value of the person.
(Rabbi Yosef Leib Bloch - Shiurai Daas; Kol Tzofayich; Gateway to Happiness, p. 122)