Why Do People Cheat? Motives, Opportunity, Relationship Factors, and Research

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Author: Ukrainian Psychological Hub · Published: September 27, 2026 · Editorial Policy

People cheat for multiple, often overlapping reasons. Research does not support one universal cause of infidelity, and it does not support the idea that every affair is simply a symptom of an unhappy relationship. Studies identify relationship-related motives such as anger, neglect, loss of love, low commitment, and sexual dissatisfaction, alongside motives and conditions that can exist even when the primary relationship is not globally distressed: desire for sexual variety, self-esteem or validation, attraction to an alternative partner, opportunity, and situational factors.

The strongest evidence points to a multilevel explanation rather than a single personality type or relationship defect. A systematic review of 82 quantitative studies found that infidelity was associated with factors operating at individual, couple, social, and contextual levels, while also emphasizing substantial inconsistency across studies. That matters: an association can change the probability of infidelity without determining what any particular person will do.

This article focuses on why infidelity occurs: motives, opportunities, relationship factors, and research-supported correlates. For the broader definition and boundaries of cheating, see What Is Infidelity? Meaning, Types, Examples, and What Research Shows.

The Short Answer: Why Do People Cheat?

People may cheat because of problems within a relationship, because of what they want or how they respond to alternatives, because an opportunity becomes available, or because several of these factors converge. The same outward behavior can therefore arise from very different psychological and relational pathways.

One influential study asked 495 people who reported having been unfaithful about their own motives. Selterman, Garcia, and Tsapelas identified eight empirically distinguishable motive domains: anger, sexual desire, lack of love, neglect, low commitment, esteem, sexual variety, and situational factors. The sample was mostly young adults and relied on retrospective self-report, so the eight categories are a useful map of reported motives rather than a universal taxonomy of every affair.

A motive is also not the same thing as a cause. “I felt neglected” describes how a person interprets part of their experience; it does not show that neglect mechanically produced infidelity, that the partner was objectively neglectful, or that another person in the same circumstances would make the same decision.

Motives, Predictors, and Opportunities Are Different Things

Research on infidelity often mixes three kinds of explanation. Motives are the reasons people report for their own behavior. Predictors or correlates are variables statistically associated with a greater or lower likelihood of infidelity. Opportunities are circumstances that make an outside relationship easier to begin, continue, or conceal. These categories can overlap, but they answer different questions.

This distinction is especially important because infidelity research is methodologically heterogeneous. A 2024 systematic review and meta-analysis covering 305 studies and more than 500,000 respondents found wide variation in how researchers define and measure infidelity, with sexual infidelity studied far more often than nonsexual forms. Anonymous measurement, convenience sampling, and unclear operational definitions can all affect estimates and associations.

So when research finds that lower commitment, greater opportunity, or a particular trait is associated with infidelity, that finding should be read as a change in risk at the group level. It is not a diagnostic test, a proof of motive, or a way to identify an individual who will cheat.

Eight Motives Identified in Infidelity Research

Anger and retaliation

Some people report cheating while angry at a partner or as retaliation for a perceived betrayal, conflict, or injury. In the Selterman study, anger emerged as a distinct motive rather than merely a version of sexual desire. It can involve an attempt to hurt the partner, restore a sense of power, or act on resentment.

Anger may help explain a person’s stated motive, but it does not make infidelity inevitable. Conflict occurs in many relationships without infidelity, and describing anger as a motive does not transfer responsibility for the decision to the other partner.

Sexual desire

A person may experience strong sexual desire toward someone outside the relationship or perceive a mismatch between desired and actual sexual experiences. Sexual desire is one of the recurrent motives in self-report research, but its presence does not imply that the primary relationship was sexless or globally unsatisfying. Attraction to other people can occur within committed relationships; how a person acts on that attraction is a separate behavioral question.

Lack of love or feeling emotionally disconnected

Some people who cheat report feeling that they have fallen out of love with their primary partner or that the relationship no longer feels emotionally connected. In motive research, lack of love was distinguishable from neglect and low commitment. That separation is useful because a person can feel emotionally detached while still remaining structurally committed to a relationship, or feel neglected without believing that love has disappeared.

Later work using the same broad research program found that motives mattered for how affairs unfolded. Dyadic motives such as anger and lack of love were associated with longer affairs and greater likelihood of primary-relationship dissolution. These are associations within a particular sample, not fixed outcomes for all couples.

Neglect or unmet relational needs

Neglect is another frequently reported motive: the person feels ignored, underappreciated, lonely, or insufficiently attended to. Research can document that people give this explanation and that relationship quality is associated with infidelity in some samples. It cannot establish that one partner’s unmet need caused the other partner to violate an agreement. People can respond to dissatisfaction through communication, boundary changes, therapy, separation, or many other choices.

Low commitment

Commitment refers to investment in maintaining the relationship and prioritizing it over alternatives. Lower commitment has repeatedly been associated with greater infidelity risk. In a study of romantically involved adults, sociosexuality and commitment were both related to sexual infidelity, with lower commitment playing an important role in whether people maintained exclusivity.

A study of 252 romantically involved adults recruited from a dating website for people already in relationships found that less commitment and more unrestricted sociosexuality were associated with sexual infidelity. The specialized sample limits generalization, but the result fits a broader literature connecting commitment with relationship-maintenance behavior.

Esteem, validation, and feeling desirable

Some people report cheating partly to feel attractive, wanted, popular, or valued. Selterman and colleagues labeled this an esteem motive. The important distinction is between a motive and a stable trait: seeking validation in one episode does not by itself demonstrate chronic low self-esteem, narcissism, or a mental disorder.

Population-based work also shows why simple explanations such as “people cheat because they have low self-esteem” are too strong. In a U.S. study of 2,291 married individuals, self-esteem did not uniquely predict sexual infidelity after marital dissatisfaction and other variables were taken into account.

Sexual variety

A desire for sexual novelty or a greater number or range of sexual partners can motivate infidelity for some people. This motive can exist independently of whether the person describes the primary relationship as unhappy. It is especially important for correcting a common assumption: not every affair is an indirect complaint about the primary partner.

Research on sociosexual orientation—the degree to which a person is comfortable with sex outside committed relationships—also supports the relevance of individual differences in openness to uncommitted sex. In Selterman and colleagues’ motive study, unrestricted sociosexual orientation was associated particularly with sexual-variety motives. This is a probabilistic association, not a prediction that someone with an unrestricted orientation will be unfaithful.

Situational factors

Some participants describe infidelity as strongly tied to a particular situation: intoxication, travel, stress, a party, sudden access to an attractive alternative, or an encounter that escalated in ways they had not planned. Situational explanations are psychologically meaningful because behavior is influenced by context. They do not erase agency or responsibility.

In follow-up analyses, situational motives were associated with shorter affairs, less satisfying affair sex, and lower rates of disclosure and primary-relationship dissolution. Again, those are sample-level patterns, not a template for judging any individual affair.

Opportunity Matters More Than Popular Explanations Often Admit

An affair cannot occur without some form of access to an alternative partner, and opportunity is one of the clearest contextual themes in the literature. Opportunity can mean frequent contact with potential partners, private time, travel, a social environment that facilitates secrecy, or technologies that make connection easier. Opportunity does not cause infidelity by itself; millions of people encounter attractive alternatives without crossing relationship boundaries. It changes the environment in which decisions are made.

Nationally representative U.S. research has long found that opportunity belongs in the explanatory model. In married and cohabiting Americans, greater sexual opportunity was associated with sexual infidelity alongside permissive sexual values, stronger sexual interests, lower relationship satisfaction, and weaker network ties to the partner.

A broader research review likewise concluded that prediction requires attention to individual, relationship, and contextual variables rather than a single cause. Fincham and May’s review specifically highlighted relationship context, demographics, and changes in opportunities created by the internet.

Opportunity is therefore best understood as an enabling condition. It can lower practical barriers to infidelity or increase exposure to alternatives, while commitment, personal values, attraction, relationship dynamics, and moment-to-moment choices still matter.

Relationship Factors: Important, but Not a Complete Explanation

Relationship dissatisfaction

Lower relationship satisfaction is one of the most frequently studied correlates of infidelity, and several population and couple studies find an inverse association between relationship quality and extradyadic sex. But dissatisfaction is neither necessary nor sufficient. Many dissatisfied people do not cheat, and some people who cheat report being relatively satisfied with their primary relationship.

For example, Mark, Janssen, and Milhausen studied 918 people in monogamous heterosexual relationships and found that predictors differed across men and women; among women in that sample, lower relationship happiness and lower sexual-attitude compatibility were associated with infidelity. The regression models explained only a minority of the variance, which is another reminder that no compact set of variables captures every case.

More recent evidence also complicates the “bad relationship causes cheating” story. A 2023 study of people who had registered on Ashley Madison to seek affairs found that low relationship quality was not a major driver of affairs in that selected sample. That sample is not representative of all people who are unfaithful, but it directly demonstrates that infidelity cannot be reduced to relationship dissatisfaction.

Sexual dissatisfaction and compatibility

Sexual dissatisfaction, sexual incompatibility, or desire discrepancy can be part of the context for some affairs. Research supports associations in some samples, yet those variables are not interchangeable with motive. A person can be sexually dissatisfied and remain faithful; another can be sexually satisfied and still seek novelty or another partner.

This is why “the sex must have been bad” is not an evidence-based conclusion from the fact of infidelity alone. A single affair does not reveal the primary couple’s sexual functioning, just as relationship satisfaction scores do not reveal why a particular person made a particular choice.

Conflict, resentment, and disconnection

Ongoing conflict and emotional disconnection can create a relational context in which outside intimacy feels more attractive or the primary bond feels less protected. They also overlap with reported motives such as anger, neglect, and lack of love. But studies often rely on cross-sectional or retrospective data, making directionality difficult to determine: relationship distress can precede infidelity, follow it, or both.

A 2024 study using a U.S. probability sample of married couples found that reported and suspected extramarital sex were both inversely associated with current relationship satisfaction. Because the study examined associations, it does not establish a one-way causal sequence from dissatisfaction to infidelity.

Individual Differences Can Shift Risk Without Creating a “Cheater Personality”

Infidelity research has examined personality traits, sexual excitation and inhibition, sociosexuality, religiosity, attitudes toward monogamy, impulsive or regretful sexual behavior, and many other individual variables. Some show associations in particular samples. None provides a clinically valid personality profile that can identify a future cheater with certainty.

The 2019 systematic review found inconsistent results across many individual-level variables and emphasized the interaction of multiple ecological levels. Haseli and colleagues also noted that heterogeneity in definitions and analyses prevented a straightforward synthesis of effect sizes.

It is therefore more accurate to say that certain traits, attitudes, sexual preferences, or behavioral tendencies can correlate with infidelity under some conditions. A correlation is not a diagnosis, and it is not a moral category. Infidelity itself is not a mental disorder.

Sociosexuality

Sociosexuality is among the more conceptually direct individual-difference variables because it concerns openness to uncommitted sexual relationships. More unrestricted sociosexuality has been associated with infidelity behavior and with motives related to sexual variety. Yet relationship commitment can still shape behavior among people who are open to casual sex.

Personality and self-regulation

In Mark and colleagues’ study, sexual excitation/inhibition patterns and a tendency toward regretful sexual behavior during negative emotional states were among predictors of sexual infidelity. The authors found sexual-personality variables more informative than the demographic variables they tested. The study does not support labeling people as impulsive, disordered, or incapable of fidelity based on one behavior.

What About Attachment Styles?

Attachment is relevant to infidelity research, but it should not be used as a catch-all explanation. A 2024 systematic review and meta-analysis of 17 studies involving 13,666 participants found that attachment anxiety and avoidance were each associated with marital infidelity, with a modest combined correlation. Association does not establish that insecure attachment causes infidelity, and many people with insecure attachment patterns do not cheat.

The broader meaning of anxious, avoidant, fearful-avoidant, and secure attachment belongs to the Adult Attachment Styles topic. See Attachment Styles in Adults: The Four Patterns, Two Dimensions, and What They Mean. Within this infidelity cluster, attachment-specific evidence is covered in Attachment Styles and Infidelity: What Research Does—and Does Not—Show, so the general motives article does not turn attachment into a universal explanation.

Do Demographics Explain Who Cheats?

Age, gender, marital status, education, income, religiosity, cultural norms, and other demographic variables appear in many infidelity studies, but their associations depend heavily on the population, period, definition of infidelity, and statistical model. Treating a demographic group as inherently more unfaithful converts population-level variation into a stereotype.

The methodological problem is especially important here. Warach and colleagues’ 2024 review found widespread demographic homogeneity and measurement ambiguity across the literature. Results from one country, age group, online sample, or definition of infidelity should not be treated as universal human constants.

For an individual relationship, demographic statistics cannot answer the question “Will this person cheat?” They can describe patterns in samples, not read intentions or predict a specific partner’s behavior.

Why Happy People Can Still Cheat

The assumption that infidelity proves the relationship was secretly unhappy is attractive because it offers a simple causal story. Research does not justify that story as a universal rule. Some affairs are strongly connected to dissatisfaction, disconnection, resentment, or low commitment. Others are more strongly connected to variety, attraction to an alternative, esteem, opportunity, or a situational event.

The Ashley Madison study is particularly useful as a counterexample because participants were actively seeking affairs, yet poor relationship quality was not the dominant explanation in that sample. Its self-selected population means it cannot estimate what is typical in the general population, but it is sufficient to reject the claim that all infidelity must originate in a distressed primary relationship.

“Happy people can cheat” also does not mean happiness is irrelevant. Relationship quality, commitment, and sexual satisfaction are associated with infidelity in other studies. The evidence supports multiple pathways, not the opposite universal claim that relationship conditions never matter.

Why a Reason Is Not an Excuse

Psychological explanation and interpersonal responsibility answer different questions. Research can help explain why a behavior became more likely, what a person says they were seeking, and which relational or situational conditions were present. It does not decide whether violating a relationship agreement was justified.

That distinction also prevents blame from being displaced onto the betrayed partner. Relationship problems can be jointly created and jointly experienced; the decision to conceal, deceive, or cross an agreed boundary belongs to the person who made that decision. Understanding context can be useful without treating context as compulsion.

If the relationship involved coercion, threats, stalking, or violence, safety takes priority over reconciliation or attempts to obtain a perfect explanation for the infidelity. In unsafe relationships, explanations should not become pressure to confront a partner or remain in the relationship.

What Research Cannot Tell You From Infidelity Alone

Infidelity does not, by itself, establish a psychiatric diagnosis, a personality disorder, sex addiction, narcissism, attachment disorder, compulsivity, or an inability to love. Those claims require separate evidence and, where relevant, clinical assessment.

It also does not prove that the betrayed partner was inattentive, sexually inadequate, insufficiently attractive, or responsible for the affair. Relationship dissatisfaction may be one factor in some cases, but infidelity occurs through multiple pathways, and the same relationship conditions can lead different people to very different choices.

Finally, infidelity cannot be reverse-engineered from “signs.” Increased phone privacy, schedule changes, emotional distance, or new routines can have many explanations. The present article addresses motives and associated factors after infidelity is known; it does not turn behavioral changes into proof that cheating occurred.

How to Think About the “Why” After Infidelity

For someone trying to understand a specific affair, the most useful question is usually more precise than “Why do people cheat?” Research suggests separating several layers: what the person says they wanted or felt; what was happening in the primary relationship; what opportunity or alternative relationship was available; what individual tendencies or values were relevant; and what choices allowed the behavior to continue.

A coherent explanation can contain more than one motive. Someone may feel neglected, be attracted to a coworker, enjoy the validation of being desired, have low commitment at that point in the relationship, and encounter repeated private opportunities. Reducing that sequence to one word such as “boredom” may feel neat while explaining very little.

The goal of a good explanation is not to produce a story that makes the betrayal acceptable. It is to identify the conditions, motives, decisions, and meanings accurately enough that the people involved can make informed decisions about what happens next. Questions about recovery, rebuilding trust, reconciliation, or therapy have their own evidence base and belong to the recovery and treatment nodes of this cluster.

Frequently Asked Questions

Why do people cheat on someone they love?

Love and fidelity are related concepts, but they are not the same behavior. A person can report love for a partner and still act from sexual desire, variety seeking, anger, validation needs, low momentary commitment, opportunity, or another motive. Some people also report lack of love as a motive, so the meaning varies by case. The fact of infidelity alone cannot determine whether love was present or absent.

Do people cheat because they are unhappy in the relationship?

Sometimes relationship dissatisfaction, neglect, conflict, sexual dissatisfaction, or loss of love is part of the pathway. But research also identifies non-dyadic motives and samples in which low relationship quality was not the major driver. “Unhappy relationship” is therefore one possible context, not a universal explanation.

Does alcohol cause cheating?

Intoxication can be reported as part of a situational motive and may affect judgment or inhibition, but it is not a complete causal explanation. In motive studies, situational factors form one category among several. Being intoxicated does not mean infidelity was inevitable or remove responsibility for behavior.

Is low self-esteem the reason people cheat?

It can be relevant when a person seeks validation or esteem, but low self-esteem is not a universal cause. In the population-based married sample studied by Whisman, Gordon, and Chatav, self-esteem was not an independent predictor once marital dissatisfaction and other variables were included.

Do insecure attachment styles cause cheating?

No causal conclusion follows from the available association data. Meta-analytic evidence links attachment anxiety and avoidance with a higher likelihood of marital infidelity at the group level, but the effect is probabilistic and many people with insecure attachment patterns remain faithful. Attachment should not be used as a diagnosis or destiny statement.

If someone cheated once, will they always cheat again?

No. Prior infidelity is a risk marker, not a destiny. In a longitudinal study following 484 adults across two relationships, people who reported extradyadic sexual involvement in the first relationship were about three times as likely to report it in the next relationship as those who had not. That finding does not mean every person who cheats will repeat the behavior. Repeated infidelity is the separate canonical focus of INF-14.

Is cheating a mental disorder?

No. Infidelity is a relationship behavior and boundary violation, not a DSM or ICD diagnosis. A person who cheats may or may not have a mental health condition, just as a person who remains faithful may or may not have one. Clinical diagnoses require their own criteria and assessment.

Bottom Line

People cheat for different combinations of motives, relationship conditions, individual differences, and opportunities. The best-supported scientific view is multilevel: anger, neglect, lack of love, low commitment, sexual desire, sexual variety, esteem, and situational factors can all matter, while relationship satisfaction, sociosexuality, attachment, sexual self-regulation, values, and access to alternatives can shift risk in some populations.

None of these variables is a deterministic cause. Infidelity cannot be explained reliably by one personality type, one relationship problem, one attachment style, or one demographic category. Research is most useful when it clarifies the range of pathways and the strength of the evidence, while leaving responsibility for a specific decision with the person who made it.