Know-it-alls are those irritating people who act as if they are experts on every topic — even when evidence and behaviors prove otherwise.
They demonstrate their self-ascribed superiority in a wide variety of ways, including dominating conversations, offering unwanted advice, being argumentative in meetings and bossing loved ones and co-workers around. They can also be condescending, challenge authority figures and engage in pointless debates.
Know-it-alls may act cocky. But that doesn’t mean they have an abundance of self-confidence. In fact, know-it-alls sometimes struggle with low self-esteem and use their braggadocio to prove to others that they are smarter than they are. It can also mask underlying anxiety and increase when they feel uncomfortable.
Know-it-alls may have a cluster of personality characteristics, including impulsivity, poor listening skills and an inability to read social cues. These could be symptomatic of certain mental disorders, such as attention deficit hyperactivity disorder or narcissistic personality disorder.