There are many forms of self-harming behaviour and numerous reasons why self-harm begins. One of the most common elements associated with self-harm is 'compulsion'. Compulsive behaviour can be seen most clearly in conditions such as Trichotillomania, where the sufferer repeatedly pulls hair from the scalp, eyebrows and/or eyelashes. It is unclear why this problem arises or why it seems to involve an almost overwhelming compulsion. The sufferer may often pull out hairs in a trance-like state (daydream) and become almost incapable of acknowledging their actions until they return to conscious awareness (return from their dream-like state). This compulsion can be so strong that some people may resort to radical solutions such as head shaving - in order to stop their self-harming behaviour.

The result of chronic hair-pulling can frequently cause extreme embarrassment and is often unfairly judged by others. Societal attitudes may lead sufferers to feel guilty or ashamed, and even depressed or withdrawn. When people feel low, they often repeat the behaviour that caused the original problem, which may in turn compound their suffering. It is a strange irony that repetitive and familiar behaviour is often experienced as source of 'comfort'. Although, this may explain why infants repeatedly suck their thumbs or older children bite their nails when feeling anxious or lonely.

It is possible that extreme compulsive behaviour may be triggered by traumatic life events. For example, physical or mental abuse, family conflict, neglect, separation or loss may be contributory factors. Negative stress caused by excessively busy lives may also result in a need for 'comforting' behaviour. Therefore, compulsive behaviour should not necessarily be seen as 'abnormal' or requiring a 'psychiatric diagnosis', but may simply be a coping strategy for adverse life events/circumstances.

Clearly, when coping strategies become exaggerated by overwhelming emotional difficulties, they can appear more complex and problematic to understand. For example, it may be difficult to view compulsive self-injury, by cutting or burning, as a means of 'comfort'. However, when individuals experience continuous conflict within personal relationships, or perhaps bullying at work, extreme reactions may be understandable. By repeating familiar behaviour - however extreme - there may be a sense of comfort. Therefore, whatever the form of self-harm, and however it begins, it invariably develops into a compulsive need to repeat a pattern of behaviour, which appears to offer some relief.