Inferiority complex refers to low self-esteem. According to the theory of psychologist A. Adler, inferiority complex plays a significant role in the psychological development of an individual. According to Adler, everyone is born with physical or psychological deficiencies, which determines the subconscious existence of inferiority complex. The way in which each person resolves his feelings of inferiority influences his behavioral patterns. The occurrence of many psychopathological phenomena is related to the mishandling of feelings of inferiority. According to Erikson's theory of personality development, the ages of 6-11 are the critical stage that determines whether a person's psychological tendency is to be studious and upwardly mobile or to have low self-esteem and self-loathing.

The inferiority complex is a central concept in Adler's book Personal Psychology. He believed that the desire for "superiority" originated in a person's sense of "inferiority," and that a person's sense of inferiority originated in incompetence at an early age. Children's fight against inferiority complexes is called "compensatory action". Compensatory action is the basic motivation that drives a person to excellence.

Interestingly, Adler's conceptualization of the inferiority complex had a lot to do with his personal upbringing. At a young age, he had an older brother who was taller, more accomplished, and smarter than he was, causing him to live in his brother's shadow from an early age. It was with a determination and perseverance to catch up with his brother that Adler continued to challenge himself until he finally achieved much more than his brother.