Shoplifting is a crime, but for many, it's also a compulsion and an addiction. As the Mayo Clinic points out, kleptomania is an impulse control disorder. It causes people not only to steal, but to continue doing it. For retailers, this kind of person is a major headache.
As loss prevention professionals know, one of the main problems with habitual shoplifters isn't just that they steal frequently, but that they're very good at getting away with it.