The Loophole and how MIB was wrong
Here is my first theory ever on this site so if there is something wrong feel free to be ruthless in the comments section. I haven’t seen this theory before on this site, if it is let me know and post a link in the comments.
The MIB wants Jacob dead. However, he must follow some rules. They are that only a candidate can kill Jacob and that if Jacob is killed, a remaining candidate will replace Jacob very quickly. As well, if all candidates die, Jacob can’t be killed. This was a problem fo MIB because he were to convince a candidate to kill Jacob, another candidate would become the new Jacob with a new 360 candidates. Thus this would create a never ending cycle in which MIB never gets rid of the ‘Jacob presence’ on the island.
MIB’s loophole was that he would wait until there was one candidate remaining and convince that candidate to kill Jacob. By killing jacob this person is no longer a candidate, so there is no one to replace Jacob, thus MIB finally removes the ‘Jacob presence’ from the island.
Ben was not the remaining candidate (we’ve seen linus as one of the 360 numbers, so I’m assuming its ben and not Roger) but MIB thought he was. We know there is 6 remaining candidates (Kate, Jack, Sawyer, Sayid, Hurley, Kwon) and all 6 of these were in the 70’s during the incident (Kwon= Jin) and afterwards there bodies would have disappeared. I think MIB believed they died during the bomb explosion. As well, Richard told Sun (with MIB listening close by) that Richard saw them all die, so MIB knows they haven’t been able to avoid both him (MIB) and Richard for 30 years, so they are dead. This leaves Ben as the last candidate.
When Jacob said they’re coming, he meant the 6 candidates, which explains why MIB was so freaked out by those words. He now realizes that someone can replace Jacob. He knows that he only has a small amount of time until one of them replaces him, which is why he is in such a hurry to get off the island. He only has a certain amount of time until a new Jacob stops him from leaving.
Thanks for listening, now feel free to prove me wrong.