DESIRES

The starting point of all achievement is desire. Keep this constantly in mind. Weak desires bring weak results, just as a small fire makes a small amount of heat. — Napoleon Hill

Many characters had strong feelings of wanting to have something or wishing for something to happen. Ben informed Locke that the Island was a metaphoric "magic box" where wishes could be granted. In Locke's mind, he wanted to have a showdown with his father. He believed the island granted him that wish.

But desires can also include emotional feelings, sexual wants or an acceptance to belonging to someone else. Kate had numerous sexual relationships during the series but was left with an unfulfilled desire for lasting happiness.

Desire could also be the quest for status or achievement. Charlie always wished to be a rock star, and for one fleeting year he lived his dream. But that dream collapsed quickly under the trappings of stardom. On the opposite end, Hurley tried to run away from his fame and fortune.

Maybe opposites do attract like magnets.  Charlie wanted the fame and fortune but Hurley despised it. On the island, they became good friends.  Kate was always looking to run away from her problems while Jack ran head first into problems in order to solve them. The same could be true with Sawyer and Juliet. Even people in a close relationship had polar opposite beliefs. Rose was a realist on her cancer fate, while Bernard was a dreamer looking for a medical miracle in any corner of the planet. Sayid did the dangerous, hard, dirty work while Shannon was the rich girl who would not lift a finger to help another person.

Some people believe the whole story was just about the main characters finding their "soul mates."
This generalization has too many exceptions. Rose and Bernard were already soul mates before coming to the island. Locke and Boone never found their soul mates because they were alone in the end church. 

Was the final bonding moment commonality? The reason Charlie gravitated towards Claire and her baby was that Charlie was alone in the world. He wanted to have a family, his own family. But his drug addiction and fleeting fame made it impossible for him to correct his path. Claire was also on a downward path. Her car accident destroyed her family relationships with her mother and sister. Her boyfriend dumped her. She wanted to have her own stable family life, but thought she could not do it alone. 

The one common trait Hurley and Libby had was that they were both institutionalized at a mental hospital. It was strange that Hurley never recognized Libby from their time together in the same day room at Santa Rosa when the Tailies were reunited with the beach survivors. And we really have no motivations or desires from Libby that matches what Hurley was thinking or feeling about his life.

Then again, one would be hard pressed to find anything in common between Jack and Kate or Sawyer and Juliet.  Medical professionals whose oath is to do no harm are matched in the after life with murderous criminals. Were Kate and Sawyer the best Jack and Juliet could do?

Maybe a closer analogy is that the island's wishing well was more like an internet dating/match site. There may be some good matches, but most of the output data is just random pairings.

THE NUMBERS: THE KEY AND THE BOX

References to LOST's mythical Numbers and the tie to a forgotten metaphor:

The Numbers were stamped on the Hatch door. The Hatch was created in the 1970s before the Purge (around 1979). When Hurley saw the numbers on the Hatch door, he tried to stop Locke from opening it because the Numbers were cursed.

Sam Toomey was a Pacific naval officer who heard the Numbers during his time at a listening post, some 16 years before Flight 815 crashed on the island (around 1988). His widow said that Sam used the Numbers, which brought him bad luck. Eventually, Sam committed suicide.

Around the same time, Rousseau and her crew her the Numbers on a radio transmission. When they were shipwrecked on the island, they traced the transmission to a radio tower near the Black Rock. Soon, Rousseau said her crew got "sick" and died. She went to the tower to change the message from the Numbers to her distress call. She also believed that the Numbers caused bad luck and her pain.

Leonard, a patient at the Santa Rosa Mental Hospital, heard the Numbers from Sam. Hurley met Leonard at the SRMH. Leonard would constantly repeat the Numbers over and over and over again. When Hurley goes to the hospital to tell Leonard that he used the Numbers to win the lottery in 2004, Leonard becomes hysterical, screaming Hurley had "opened the box" and he must get away from those Numbers or it "won't stop."

So, Leonard basically told Hurley that the Numbers were a KEY that unlocked a BOX that would cause a string of BAD events.

The only other major reference to a BOX was when the term was used by Ben to explain one of the secrets of the island to Locke in "The Man from Tallahassee:"

Benjamin Linus: Let me put it so you'll understand. Picture a box. You know something about boxes, don't you John? What if I told you that, somewhere on this island, there is a very large box and whatever you imagined, whatever you wanted to be in it when you opened that box, there it would be? What would you say about that, John?

The man Ben claimed to have delivered from the Magic Box was Anthony Cooper, Locke's father. Cooper said that he was driving along, was hit in a car accident, and then suddenly found himself bound and gagged in the room. Cooper believed he had died, and that they were all dead.

When Locke pressed Ben for more about the Magic Box in "The Brig," Ben snapped back that "the Box is a metaphor, John." Despite this, Ben continued to maintain that by some agency things that people on the island wanted or needed would show up.

Tracing back the Numbers as referenced in the show, the Numbers appear earlier than Rousseau or Hurley's knowledge of them. In the Hatch, the Numbers were used as code to ward off a disastrous event. In ancient cultures, numbers, chants, and spells were keys used to ward off evil spirits.