Quest of the Avatar

The Quest of the Avatar is the quest to be not a role model for one or two virtues, but for all of them at the same time. To prove him/herself to be virtuous by nature and show the people of the land the way of enlightenment and virtue. Lord British writes about it:

"The Quest of the Avatar is the search for a new standard, a new vision of life for which out people may strive. We seek the person who can become a shining example of our nation and guides us from the Age of Darkness into the Age of Light."

The original Quest of the Avatar in Ultima IV included to become a partial Avatar in all eight virtues, and then to discover the Codex of Ultimate Wisdom in the depths of the Abyss. But this was hardly the end. The Quest of the Avatar is never ending. Always the goodness and virtue of an Avatar is tested. It is a never ending struggle against the darkness in man's heart. Always an Avatar has to prove again and again to the people of the land that he/she is worthy of being an Avatar.

Trivia
This segment of Guardian's origins is highly controversial. This theory practically nullifies the whole purpose of the Quest of the Avatar. Ultimately, this origin theory is the result of several plot changes throughout the Guardian saga. All those were results of cut plot elements.
 * The Guardian was created by the loss of negative energy when the Quest of the Avatar was completed. That energy needed to go somewhere and what happened was, it manifested itself into a Negative Avatar.  The Guardian now embodying all the evil our hero once had.