The cognitive dissonance theory states that dissonance is most likely to occur when

The cognitive dissonance theory states that dissonance is most likely to occur when an individual must choose between two incompatible beliefs or actions.

In this situations an individual does something that is personally disagreeable.

The cognitive dissonance theory was developed by Leon Festinger (1957). The theory focuses on creating knowledge about important psychological processes of individuals.

Cognitive dissonance is most likely to occur when a person simultaneously holds two or more conflicting thoughts or beliefs. When an individual experiences cognitive dissonance, it makes him or her feel uneasy and uncomfortable and in turn, alter one of the beliefs or behaviors in order to restore balance and resolve the discomfort.