What is the meaning of Jacob's line, "What about you?"

Like many other unanswered questions, there's no definite answer to this one. I'll offer a couple of interpretations, however:

1. If you take into account the context of the scene, Ben was talking about Locke, specifically he was comparing him to himself. However, unbeknownst to him, "Locke" in the room was in fact The Man in Black at the time, an entity that in many ways represented the evil counterpart of Jacob.

   Jacob, aware of this, asked Ben "What about you?" in hopes of setting Ben straight and making him realise what he's comparing himself with, i.e. "What about you? Do you want to be the monster he is?"

   We have two possibilities regarding this scenario:

   • Jacob knew Ben had not realised the true nature of "Locke" by that point, but was still hoping Ben knew on some level of all the bad things he had done.
   • While less likely, Jacob may have assumed Ben was aware of the true nature of "Locke" and was just making a huge mistake.

2. Jacob was trying to make Ben realise he's not the "higher power" with all the answers Ben assumed him to be. Ben's questions were related to what was wrong with him, something Jacob had no way of knowing or responding to.

3. Jacob was trying to provoke Ben into killing him, possibly in hopes he would resist the temptation.

4. Jacob was dismissing Ben and truly didn't care about him. Ben was a murderer who, while manipulated at times by The Man in Black, displayed sociopathic tendencies on his own free will and Jacob simply didn't believe he deserved any kind words, even if that means he'd die.

In retrospect, it appears the point of the scene was simply to foreshadow that Jacob, who was strongly hinted to be a godlike being or even God personified until that point, was merely a man who, while possessing some sort of supernatural power, was far from all-knowing and all-powerful (as confirmed to a degree in Across the Sea).

Therefore, in that scene, he either:

• Completely misjudged Ben's nature and intentions, assuming he wouldn't kill him.

• Didn't truly care whether he lived or not, realising that The Man in Black will just keep trying until he's dead.

• Was largely unaware of the influence his actions had on the survivors and the expectations some of them had of him.

Researching lost and thought I'd look up what people thought of this line, these are great answers, but I think you missed one:

Jacob realised that Locke had found the loophole that allowed him to kill him and already accepted the fact that he was going to die, so he didn't try to talk to Ben in any convincing way. He just answered the questions he knew that Ben would continue to ask himself even though might not immediately realise that "what about you" is the actual answer. Jacob did this tactic earlier in this episode when he was visiting lol the other characters. When he gave jack the apolo bar he said that "it just needed a little push" in the same style, and those world's stuck with Jack and helped him

Ben was a manipulator, intriguist, sociopath and above all he thought that the world revolved around him even though he was already aware that this was not the case. Jacob tried to open his eyes for one last time, trying to explain him that the World / Island was about everyone, not just about Ben.

I have just finished Lost for the second time and I remember thinking the same thing the first time I watched Jacob's line he spoke to Ben "what about you?" The whole time Ben was on the show, I felt he was very narcissistic. So when Jacob asked, "what about you?" Was his way of saying "it's not about you, so get over yourself." That's the way I felt about it anyway.