To understand why the idea of an addictive personality is flawed, it’s important to first understand what psychologists mean when referring to personality.
Personality is comprised of broad, measurable, stable, individual traits that predict behaviour. So by definition, engaging in excessive behaviours cannot be considered a personality trait.
Though, there are personality traits that are associated with addiction.
Neuroticism is one of the “big five” personality dimensions. These are the five core traits that drive behaviour. They include openness to experience, conscientiousness, extraversion/introversion, agreeableness and neuroticism.
People who score high in neuroticism tend to be easily emotionally aroused. They are also more likely to engage in a number of excessive behaviours, including: over-eating, excessive online gaming, social media over-use and substance dependence.
People who are highly neurotic might engage in excessive behaviours to help manage their emotions. Neuroticism has also been associated with a range of mental health conditions, which could lead one to wonder whether addiction is caused by mental illness.
There is evidence of this for some people. In these cases people’s addictive behaviour reduces negative emotions caused by the mental illness. Though it could also be that certain personality factors such as neuroticism predispose a person to both mental illness and addiction separately.