Just as important as knowing what gift God has given you is knowing which gifts He hasn't give you. Many Christians try for years to function with gifts they never had in the first place, and this doesn't do the Lord's work much good. It's like trying to hear something with your knee or throw a ball with your nose. Knees and noses are better off doing other things.
Father: Why did you not become mine God!? God: Because you did not believe in me.