Lying is a valuable tool in our survival kit. We can spare someone's feelings or build social standing. Lying can keep us out of trouble or even save our lives.

Practicing deception starts as early as six months of age such as fake crying or laughter. But people only start to get good at it after another four years where they learn to let go of the unbelievable lies and settle for what kind of lies work. 

Lying keeps us hooked because we enjoy the reward. The outcomes are unpredictable.
Lying is reinforced every time we get away with it.