Most people rarely lie and therefore operate with a "truth bias," assuming others are also being truthful. This cognitive default, while efficient for most interactions, becomes a major vulnerability that people with dark personality traits exploit. They can lie frequently because it rarely occurs to others to question them.

Contrary to the popular belief that power corrupts, research suggests it acts as an amplifier. If a person is already "pro-social"—oriented towards helping others—power can increase their empathy and effectiveness. If they are selfish, power will magnify those negative traits.

Counterintuitively, individuals with severe personality disorders do not respond positively to empathy and nurture. These pro-social behaviors actually make them more exploitative. They are often immune to punishment and perceive empathy as a vulnerability in others, which they then leverage for their own gain.

People with dark personality traits often self-report them honestly on questionnaires. They don't see being callous, manipulative, or superior as negative characteristics, so they feel no shame or remorse in admitting to them.

Companies often cannot differentiate between healthy confidence and narcissism. Narcissistic individuals excel at self-promotion and appearing decisive, which are frequently misidentified as leadership qualities, leading to their accelerated advancement over more competent but less self-aggrandizing peers.

Within the 'Dark Triad' of personality traits, there is a clear hierarchy. Psychopathy is an escalation of narcissism. All psychopaths exhibit pathological narcissism, but many narcissists do not possess the additional traits of psychopathy. Narcissism is a necessary, but not sufficient, condition for psychopathy.

Many white-collar criminals are otherwise intelligent, successful leaders who want their firms to succeed. Their misconduct stems from environmental pressures and psychological distance from consequences, rather than inherent malicious intent. This challenges the simplistic view that only bad people do bad things.

Successful individuals earn 'idiosyncrasy credit,' allowing them to deviate from social norms. However, observers often make the mistake of assuming these eccentricities were necessary for success. In reality, these behaviors are often tolerated or hidden until success provides the freedom to express them.

While psychopathic and narcissistic traits help politicians attract followers and media attention, these same traits make them less influential in Congress. Colleagues find them difficult to collaborate with, hindering their ability to get bills passed.