"Every conduct that is rewarded is repeated. The first time a specific conduct took place, pleasure was generated from the experience, and the brain integrated the experience into neurons associated with the memory of pleasure, causing you to naturally repeat the action because it provides a certain well-being (remember all human conduct aims toward achieving previous felt happiness and staying in this state). This is why we human beings are very habitual and always seem to repeat the same patterns of behavior over and over. This way humans are able to avoid pain at all costs, enhance their well being, but this makes you closed minded and sometimes blind to new things, new places, new people. It all depends on what the individual wants to experience in his lifetime."
introskeptic, a reflection on human conduct.