Even multimillion dollar racing yachts cannot compete with the harsh nature of the Pacific Ocean. the vast ocean and high rolling waves takes it toll on all shipping, including the large cargo container vessels. The idea of a small amateur raft being able to sail hundreds or thousands of miles to Fiji seems implausible. But at least it fulfilled one critical human element of the story: escape and rescue.
That was the key point to the start of the series. Human beings shipwrecked on an island want to go home. They need to get home. Their lives are not on the island. They would do anything to get home. Building a raft for a dangerous journey across a brutal sea makes sense when the overriding human emotion is to get home. The building of the raft made the most sense in the early story lines.
It also caused one of the first true leadership splits in the group. Michael was in charge of the ship, not Jack. Jack was really not interested in their rescue plan. Michael was motivated to take his son home. But Walt had different ideas. He did not want to live with a stranger (his father). He would rather stay on the island and create a new life since he had nothing to go home to on the mainland.
The building of the raft led to the first true betrayal. The first raft was set a blaze, which led to charges and countercharges amongst the group's alpha males. Sabotage was a volcanic destabliizer for the beach camp. Fingers were pointed at Sawyer, Locke, the Others . . . but Michael channeled his anger in order to build a second raft. It was the only thing bringing hope to the group.
When the raft set sail, it marked a turning point in the series. The show could have gone in several different directions. First, the comparison of the "good" camp life with food and shelter could have been contrasted by the harsh starvation and terror of being lost at sea for weeks on a raft that was slowly falling a part. Second, the raft could have made it civilization which could have set up the second betrayal - - - Michael and Sawyer not telling their rescuers of the island survivors. Third, and what happened, was the Others taking charge of the castaways lives. This was the flash point for serious bloody conflict between the Others and the 815ers. Why the Others would break the truce in order to kidnap Walt, who was special was unclear, considering Ben would release Walt and his father on the boat for freedom (in exchange for another betrayal, which seems now as the only real currency on the island.)
The raft symbolized freedom, escape and rescue. But in the end, the raft set in motion a series of bloody decisions leading to dozens of senseless deaths, kidnapping and torture of individuals. Walt's kidnapping led to Michael going insane with rage. His rage killed Ana Lucia and Libby. His plan to rescue Walt led to Jack, Sawyer and Kate being captured and tortured. It forever divided the beach camp and the Others as enemies.
