Oft expectation fails, and most oft there
Helena:
"Oft expectation fails, and most oft there
Where most it promises; and oft it hits
Where hope is coldest, and despair most fits."
Shakespeare's plot in this play involves a beautiful woman, Helena, who is rejected by the man she loves and will use tricks and cleverness to win his heart and hand in marriage. In this scene, Helena has followed Bertram, her object of desire, to the king's court in Paris. The king is suffering from a terminal illness, but Helena (whose recently-deceased father was a court physician) claims to have a cure, and seeks to treat him. The king has doubts, of course - the thought of a woman being a doctor and suggesting a cure was unheard of at this time. But Helena prevails through the skillful use of rhetoric, and the remark quoted here finally convinces the king to allow her to treat his illness, which she does, successfully.