While you may have heard the phrase, “Once a cheater, always a cheater,” the truth is more complicated. If someone has cheated on their partner once, it does not necessarily mean they will cheat again. That said, studies show that someone who has cheated once is three times more likely to cheat repeatedly than someone who has never done so.
Sometimes, people cheat because they feel particularly insecure and are seeking external validation. In other cases, they make an uncharacteristic decision due to a perfect storm of circumstance. In situations like these, when the motivating factors for cheating are temporary, it’s likely they won’t cheat again.
In other cases, someone might be what’s known as a serial cheater. A serial cheater is someone who consistently cheats in romantic relationships. Some people cheat multiple times because they struggle with an insecure attachment style, or other emotional issues. Some may repeatedly attempt to commit, but find that monogamy is not for them. Others may cheat because they are aroused by the experience of cheating itself.
Some serial cheaters may have narcissistic personality disorder (NPD), a condition that can lead to an exaggerated sense of self-worth and importance, a lack of empathy, and a strong need for attention. Narcissists often have troubled relationships, and may cheat on their partners because they have an insatiable need for admiration and attention, requiring validation from as many sources as possible.