Whenever I mentor people and help them discover their purpose, I always encourage them to start the process by discovering their strengths, not exploring their shortcomings. Why? Because people's purpose in life is always connected to their giftedness. It always works that way. You are not called to do something that you have no talent for. You will discover your purpose by finding and remaining in your strength zone.
John C. Maxwell (2015). “The Leadership Handbook: 26 Critical Lessons Every Leader Needs”, p.59, Thomas Nelson Inc