What was the benefit/purpose of shakespeare portraying macbeth the way he does in the play?

Lady Macbeth is the focus of much of the exploration of gender roles in Macbeth. As Lady Macbeth propels her husband toward murdering Duncan, she indicates that she must take on masculine characteristics. Her most famous speech addresses this issue. In Act I, Scene 5, after reading Macbeth's letter in which he details the witches' prophecy and informs her of Duncan's impending visit to their castle, Lady Macbeth indicates her desire to lose her feminine qualities and gain masculine ones.