LOST was a great show but some events that are crucial to the plot structure seem to have left unanswered. Please, suggest an answer if you have one.
1. How did Locke, Echo, and Desmond survive the Swan implosion? The hatch was being compressed by extreme electro-magnetic forces. The entire thing imploded. Locke, Echo, and Desmond should have all died right there. No, somehow, they are transported back outside, relatively unharmed... 2. Why were Jack, Kate, Sayid, and Hurley transported out of Ajira 316 when it crashed and back to 1977? Why didn't Sun go with them? This seems totally random. 3. The incident. I guess the island had one timeline all along and the incident referred to the bomb going off. If so, why were they transported back to 2007? 4. What was with the pregnancies?? The only reason I'm not listing this one with the other island unanswerables is because they put so much dam focus on this question. Was the MIB infecting them or was it because of the electromagnetism or what? IT was the reason Ethan kidnapped Claire, the others obsession with children, the reason Juliet was there, etc. Seems like they could have given us more.
There were also a lot of other ambiguous details about the island left unanswered. I can accept mysterious questions such as, who built the statue, where did Mother come from, why the island had the ability to time-travel, what was with the time delay between the island and the freighter, who Jacob referred to when he said they're coming, WHO WAS IN THE DAMN CABIN WHEN HURLEY OR WHOEVER LOOKED IN AND SAW THAT EYE, etc. remain up to the interpretation to the viewer but IMO the three I listed were too crucial to the chain of events to remain unanswered. Feel free to correct me or to name a few others you come up with.