Do you have a "bad" habit like biting nails, pulling out your hair or picking at your skin on your feet? Why do you do this? Is it anxiety?, boredom?, for an interesting flaw? 

I was a nail biter for 50 years and one day decided to stop biting after listening to Tony Robbins. He told a story about negotiating a contract with a multimillion dollar company. When the paperwork was presented to him to sign, a business woman refused the deal because she thought if he didn't have the discipline to not bite his nails, he was not the right man for the job. This really hit me over the head and I stopped biting my nails and have not bitten them since. 

These behaviors are repetitive type behaviors and research has been done to figure out why people have these habits even when they know it is bad for their nails, skin, hair, feet and hands. According to Researchers from the Institut universitaire en santé mentale de Montréal and the University of Montreal, Canada, women that bite their nails occurred when they were stressed, frustrated or bored. They did not bite their nails when they were not anxiety ridden or busy. However, even though these habits are repetitive, they also seem to give each person a reward. 

A researcher by the name of O'Connor (and colleagues) studied 24 individuals with these who bit their nails, pulled out their hair and picked at their skin. They then compared this group to 24 people who did not. After filling out questionnaires which attempted to promote boredom, anger, anxiety, guilt and irritability and having phone conversations with each individual Participants completed questionnaires to assess emotions such as boredom, anger, guilt, irritability and anxiety and also took part in a clinical evaluation over the phone. After that, these individuals were then exposed to different situations, to stir one of four emotions: 

1. Stress 

2. Relaxation 

3. Frustration 

4. Boredom. 

Videos for some such as of a plane crash or waves on a beach. To promote frustration, the researchers gave tasks to individuals and told them it was quick and easy when it was really difficult. Boredom was tested by leaving the participant alone in a room by themselves for around 6 minutes. 

What they found was subjects with that exhibited nail biting, pulling hair and picking their skin reported a higher eagerness to engage in such behaviors when bored or frustrated but not when relaxed. Researchers then assumed by these results that these individuals only engaged in these behaviors when under stress or bored but stated it was not simply a nervous habit. O'Connor concluded that people who engage in such behaviors have perfectionist traits. He believed that "they are unable to relax and to perform tasks at a 'normal' pace. They are therefore prone to frustration, impatience and dissatisfaction when they do not reach their goals". He also stated that these individuals get bored quicker than non-perfectionists. Even being a perfectionist (I am one myself), there are tools you can use to stop these behaviors. Meditation, exercise, patience practices can all be used to help stop these behaviors if you want to. Good luck!