Here is a comment I left on another blog, which sums up a lot of my opinion on Lost:

The entire show was an exposition on Purgatory. The entire airplane in the pilot episode crashed into the ocean killing everyone. The island was purgatory where each character could atone for their sins. Jack and his daddy issues, Kate and her daddy issues, Sawyer and his daddy issues. Desmond couldn’t finish anything so his punishment was a 108 minute torture, when he couldn’t finish that, he died again, but ended up back on the island – for another round of punishments. Everything else was either a red herring or the complicated psychodrama played out by souls looking for relief from guilt. Smoke Monster, Polarbear, Branded Shark… the Others, the Statue, Time Travel, the Dharma Initiative. A giant basket of red herrings. Purgatory is a dream, especially for the dead. Flashbacks, Flashforwards, and even the Flash-sideways were all a part of atonement, highlighting the regrets and guilts that plagued the entire airplane load of dead people. Each character got their own special version of hell to endure and we were ringside for all of it. In the end, they were all hoovered up by the most annoying ending possible for a six-year investment. “And they all died happily ever after.” At least there won’t be anything more of it, unless they hock up a movie about “Lost in Heaven”.