A candidate is a person who wants to be a leader to guide others.
A guardian is a person who is a leader who protects others.
A light is symbolic of knowledge, direction, energy and life.
A person who has both the compass and the light is truly powerful.
Locke had the compass. He knew how to use it. He was aware of the island's special powers. He wanted it to guide him to his destination (destiny). Just as magnetic north is a constant direction, the island pushed Locke towards his fateful demise.
Kate was a natural runaway, a wanderer with a keen sense of direction and tracking skills. She was a survivor throughout her troubled life. She used her internal compass not to find a destination but to flee from one. Just as our forefathers took chances and headed west into the wild unknown, Kate embraced that wild west spirit.
Sawyer also had a focal bearing in his life: to find the person who killed his family. His life's direction was formed by his own promise for revenge. He honed his own tracking skills with the southern charm of a con artist to find the man who ruined his life.
Jack was following a trail for most of his life. The trail that his father had made through the jungles of childhood. Jack was always trying to find a way to get ahead of his father's accomplishments so his father would respect his achievements. He would symbolically look to the East, where the dawn would rise on each new day, to find some hope that the light would empower him to reach his goal.
Locke's direction was north, toward the magnetism of the island's mysterious power to give his life meaning.
Kate's direction was west, to the open opportunities and freedom to run away her past.
Sawyer's direction was south, toward the slow, simmering pace of the long, cruel road of honor and revenge to release his personal demon.
Jack's direction was east, toward the dawn of a new day where he could release himself from the shadow of his own father.
Each character had their own direction. They were set to their own paths. As a result, they did not work well together because their compass points would never align. And perhaps, that was the governor that protected the light cave - - - the candidates needed each other in order to obtain both the full compass points and the light. For in the end, none of these four candidates took the place of Jacob, the island guardian, to put their own rules upon the universe.
