I remember the story of a little boy who had watched Gone with the Wind with his parents. He saw Rhett Butler say to Scarlet "I want what I want when I want it." So the next day he tried this out on the little girl who lived next door. He swaggered up to her and said "I want what I want when I want it." She looked at him and said "Well, you'll get what I got when I get it."
I'm running on self will when I want what I want regardless of what God or anyone else may want. In this condition -- consumed with my own plans and ideas -- It's only a matter of time before I'll be doing mental, spiritual, emotional and maybe even physical harm to another of God's children. I'll be like that tornado the Big Book talks about ... running through the lives of the people around me.
I learned in AA that the only solution to self will is to do God's will instead. Fortunately the instructions on how to do God's will are neatly written down in the Big Book of Alcoholics Anonymous. All I gotta be is willing, honest and open minded.