How does God define success? His measure is very different from the world's definition, and it can be summed up in one sentence: Success in God's eyes is faithfulness to His calling. Paul was a failure in the world's eyes- but not to God. even Jesus was a failure as far as most people were concerned, but " he was faithful to the one who appointed him"- and that is all that mattered.
What is your definition of success? Is it the same as God's- and are you pursuing it?
" Therefore, holy brothers, who share in the heavenly calling, fix your your thoughts on Jesus...He was faithful to the one who appointed him." - Hebrews 3:1-2