The purpose of prayer is not to persuade God to do our will.  Rather, we go to Him with what appears to us to be our symptoms so that, through His Word and divine providence, we may learn what the problem really is and be willing to do what He has revealed.  Do you really believe you and I could ever want something for our lives that was better than God desires for us?  I am convinced that through prayer and Scripture, we learn what God's will is for us, and then God gives us the grace to put His will into action in our lives.