PROGRESS TO ONE END

The key conversation between Jacob and MIB was on the beach, when the 1800s wooden ship is being brought to the Island:

MIB: I don't have to ask. You brought them here. Still trying to prove me wrong, aren't you?
JACOB: You are wrong.
MIB: Am I? They come. They fight. They destroy. They corrupt. It always ends the same.
JACOB: It only ends once. Anything that happens before that is just progress.

Who brought the people to the island? JACOB
How did the people get to the island? JACOB
What do the people do once they get to the island? Fight, destroy and corrupt.
When does this cycle end? Once.
Why does Jacob keep bringing people to the island? For Progress.

It is almost like Jacob is bringing human souls to the Island to be lab rats in a complex human mind maze. People, being human, revert to basic human, primal instincts: fighting, destroying, corrupting one another, then killing each other.

It is like a human experiment where test subjects are running through a series of tests or maze to solve the problem and get a reward. But in this case, the reward is poison or toxic. The lab mice are running around, and even if their hunger leads them to the cheese, the cheese is toxic so the human race fails (again and again). Only when a lab rat realizes that the cheese reward is not to be eaten (it is poison), does the human race find greater intelligence than primal animals. The greater intelligence is the End to unlock humanity failings.