It was done to attract us to divine love. Christ is the perfect image of who God is for creation. He is the mirror of who and what all humanity and created things are meant to be. Creatures participate in this perfection to the capacity of their natures. Humans can choose to participate in imaging God, both physically and spiritually.
Every creature is unique, gifted and living in relationship.
No human life is a mistake, because every one is uniquely gifted. The relationships of life are meant to be deepened according to the nature of the creature. This reflects the nature of God, who lives in Trinity and is therefore capable of the greatest depth of relationship. Nothing human have the ability to do has the capacity to make God do something. God is always freely choosing lover for humanity, even when we don't see that the choice is the best.