Define "Success"

Perhaps the most important characteristic of a steward is faithfulness: "Now it is required that those who have been given a trust must prove faithful" (I Cor. 4:2). Faithfulness is not a matter of results; it is a matter of dependent obedience. God knows that you cannot control other people, so he will not hold you responsible for the ultimate outcome of a conflict (Rom. 12:18). What he will look at is whether you sought his strength and guidance, remembered the freedom and power you have through the gospel, and obeyed his commands and wisely used the resources he has given you. If you have depended on him and done your best to resolve a conflict in a loving and biblical manner, no matter how the situation turns out, you will have earned that marvelous commendation: "Well done, good and faithful servant!" (Matt. 25:21a).

Taken from The Peacemaker: A Biblical Guide to Resolving Personal Conflict
by Ken Sande, Updated Edition (Grand Rapids, Baker Books, 2003) p. 40