The therapist recommended that Andrew try it for thirty days so he could experience what it was like to be sober. The therapist knew that if a heavy drinker can do this, he usually feels better—clearheaded, full of energy, better able to enjoy the simple pleasures in life—and that this feeling increases motivation for long-term sobriety. On the other hand, if a drinker can’t achieve thirty days of sobriety, it’s an indication that he no longer has full control of his drinking. That can be an eye-opening experience that may persuade a drinker to get alcohol out of his life.