Success and failure are Master words, meaning they are to be decided and defined by the Master. As Christians, we are not our own masters and thus need not be concerned with words such as “Success” or “Failure” in the worldly sense. But Faithfulness, now that is our concern as stewards.
Think of it this way, God doesn’t need you or your talents. He can do more with one act of faithfulness than you can do in 10,000 lifetimes.
Success in life, then, is simply idenitifying what God has called you to and being completely faithful in it.