Same here. For me it was being able to exercise discipline in the one area where I was lacking. Every area of my life, work, relationships, faith, finances was being negatively impacted by alcohol. No matter how much discipline I applied in these areas, there was a limit as to making them better, and it was all because one area, drinking, actually had a place in my life, and it was out of control.
So many years I tried to discipline through moderation, and failed. Once I exercised complete and total discipline by quitting completely, every other aspect of my life got better, and I am getting better at getting better each and every day.
But the biggest benefit is in being better for myself, I can be a better husband, father, and friend.