Finally, the hero returns home from the journey, having conquered obstacles both internal and external in nature, but changed. The hero now carries a personal 'wound of knowledge'---physical and/or emotional---that is connected to lessons learned on the journey and the wisdom that must now be shared with the community. But the hero chooses to returns for one reason: love.
In The Wizard of Oz, Dorothy returns to Kansas out of love, for love. In The Deathly Hallows, Harry returns to Hogwarts out of love, for love. In MockingJay, Katniss returns to District 12 out of love, for love. And in The Return of the King, Frodo, Sam, Merry, and Pippin return to the Shire, out of love, for love.
Love is the greatest gift, the greatest legacy, and the greatest lesson to be learned.
Love is what makes one a hero.