Why do we hurt ourselves?

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Evolutionary theory - and common sense - suggests that we are motivated to preserve our lives and well-being and avoid causing ourselves harm. And yet, self-destructive behaviors of all kinds are surprisingly common even among those considered to be mentally healthy. For example, chronic binge drinking, which can lead to serious health problems and even death, is rampant on American college campuses, as are disordered eating behaviors. We hurt ourselves in less overt ways as well, like sabotaging our chances of success for fear of failure, refusing to give up on a task, relationship, or investment even when it's clear that our efforts are in vain, or neglecting to seek medical attention when it is direly needed. Psychologists have argued that these behaviors are not motivated by a self-destructive impulse, as Freud suggested, but rather are a by-product of other motives and processes. These processes, reviewed by Baumeister & Scher (1988), are outlined below.

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Many self-destructive behaviors represent trade-offs: sacrificing one goal in the service of another goal that may seem, at least in the moment, to be more important. For example, a teenager may want to be healthy and take care of themselves, but also to fit in with their friends, and in some situations engaging in risky behavior may seem like the only way to gain that social approval, as evidenced by people's willingness to undergo life-threatening hazing rituals. In their article, Baumeister and Scher focus on a number of specific examples of trade-offs:

1. Self-handicapping. At times, we may create obstacles to success that can then be used as excuses for failure - for example, getting no sleep before a big exam so that failure can then be attributed to lack of sleep, not lack of intelligence. In this case, the possibility of success is sacrificed for the sake of protecting self-esteem. 
2. Substance abuse. Most substance abusers use drugs in spite of, not because of, their health risks. The primary goal is to feel good, or at least to not feel bad. The authors also argue that drug and alcohol abuse, as well as binge eating, represent attempts to escape painful self-awareness. 
3. Health care negligence. Though intended to relieve suffering, medical treatment itself can be quite painful and uncomfortable, psychologically as well as physically, not to mention expensive, inconvenient, and time-consuming. Many people go to great lengths to avoid these costs, even when that means putting their health or even life in jeopardy.
4. Face work. Studies of face work, Goffman's (1955) term for the desire to maintain a positive public image, suggest that people are willing to forego monetary compensation in order to avoid embarrassment. This tendency may play out in contexts where people hurt themselves in order to gain social acceptance or appear tough, as in the hazing example described above.
5. Shyness. As I discussed in a previous post, shyness need not be a bad thing, but it can certainly be self-defeating at times, such as when you meet the love of your life but are too shy to ask for their phone number. Shyness is seen as self-destructive to the extent that shy behavior tends to undermine people's ability to make friends and build social connections, when tragically, many shy people desperately want those connections but are afraid of being judged negatively if they take social risks (shyness in this case is seen as rooted in social anxiety and is distinguished from introversion, which involves seeking solitude by choice). 
6. Justice. Though not an official part of the list, another reason that people may choose to suffer is to punish themselves for perceived wrongdoing, thus restoring a sense of justice and avoiding punishment from others. People may also berate themselves because they believe that by doing so they will become better people. Even in the absence of guilt, some people believe that the more they suffer now, the less they will suffer later, as if everyone has a "fixed quota of suffering" that they must endure. Finally, although this is not discussed in the article, an individual may choose to suffer for the sake of someone else's well-being, donating a kidney or risking their life to save another. Altruistic self-sacrifice seems to deserve a category of its own. 

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Another class of self-destructive tendencies are counterproductive strategies, strategies of attaining a desired goal that are ineffective or likely to backfire. They are distinct from trade-offs in that self-harm generally results from factors like inadequate self-knowledge, misjudgment of ability, or unanticipated obstacles. Baumeister and Scher focus on the following examples:

1. Perseveration. We are taught that if at first we don't succeed, we should try, try again. In many cases, this attitude is helpful, but it's also important to know when to quit. Studies have found that although people with high self-esteem were more persistent in the face of failure, they also spent more time on unsolvable problems as part of a timed task, thus limiting the time available to work on solvable ones. Research also suggests that people often have difficulty letting go when they have already invested time and money into a doomed endeavor, a processes called entrapment. 
2. Choking under pressure. Tragically, it's often in those very situations where it's most important to perform well that many of us fall apart, or at least give a sub-par performance. The at-bat that will determine the outcome of the world series, the piano recital that will mean acceptance or rejection into music school, the dream job interview. In such situations, if we have prepared well, the most adaptive strategy is to let well-learned processes or responses take over, but unfortunately over-thinking is what many of us do instead.
3. Learned helplessness. While some people refuse to give up (perseveration), others give up too quickly. After repeated experiences of failure, people may grow to feel as through their efforts are hopeless, and thus stop trying. Although some argue that learned helplessness can be adaptive in the short-term by protecting the self from disappointment, in the long-term it can lead people to miss out on valuable opportunities. 
4. Bargaining. When it comes to negotiating salaries and other divisions of resources, both overconfidence and under-confidence can be detrimental. For example, failure to make any concessions on a business deal can lead someone to lose it altogether. 
5. Ingratiation. Sometimes people's efforts to please others backfire, as research suggests occurs for lower status people who try to flatter those of higher status, leading the high status individuals to perceive them as manipulative or desperate. Interestingly, doing a favor for someone can make them like you less, as it makes them feel a sense of obligation to return the favor. 

In sum, as much as we try to act in our best interest, we also sometimes behave in self-destructive ways, inadvertently creating pain for ourselves and others when that is the last thing we want to do. Most research suggests that self-harm is often a byproduct of other goals - wanting to be accepted, to feel good, to improve ourselves, or to avoid pain - rather than a primary motive itself. Even individuals who engage in overtly self-injurious behavior tend to do so for these same types of reasons, particularly the desire to escape emotional pain. Thus, our irrational self-destructive tendencies may be somewhat more rational than they seem - they serve a purpose beyond suffering for its own sake, making these habits all the more harder to break. 

The article:

Baumeister RF, & Scher SJ (1988). Self-defeating behavior patterns among normal individuals: review and analysis of common self-destructive tendencies. Psychological bulletin, 104 (1), 3-22 PMID: 3043527