Answer:
When trying to convince Macbeth to commit regicide, Lady Macbeth insults and berates him. Lady Macbeth questions his ability to do what he said he would do and she calls him a liar. Lady Macbeth then questions his manliness. "When you durst do it, then you were a man; And, to be more than what you were, you would Be so much more the man."Macbeth still isn't totally convinced, which is why he asks what will happen if they fail. Lady Macbeth simply tells her husband to "man up". If he does that, then they cannot fail.