In, Hamlet, Shakespeare gives a recipe for disaster: hubris (arrogance) leads to hamartia (a mistake) which, in turn, causes the irreversible downfall of its hero, culminating in death.
Hamlet is the only major character in the play with a conscience. In fact, his Superego is too developed. He knows too well that Claudius is an incestuous, adulterous murderer, that "Denmark's a prison," that "Frailty, thy name is woman." This, of course, inflates his moral pride to excess.
Hamlet is so bent on sending his and his father's souls to heaven and Claudius' soul to hell that he becomes unable to act. His moral reservations against personal revenge cause delay. His "holier than thou" attitude allows Claudius to maneuver, expose, and kill him. Hamlet is more interested, it seems, in instilling Claudius with guilt than he is with carrying out the Ghost's wishes. He is also too concerned over his mother's infidelity and incest. He wants to punish Claudius and Gertrude morally before punishing them physically. These are Hamlet's tragic mistakes that lead to his own death.
Hamartia is a tragic flaw in the protagonist's character that brings about their downfall. Hubris is one example of hamartia in which a protagonist's excessive pride and confidence result in their tragic downfall. Throughout the play, Hamlet's hamartia is his inability to act. Hamlet seems incapable of seeking revenge by killing his uncle. Hamlet also allows his pride to get in the way of killing King Claudius. Hamlet attempts to overstep his human authority by making sure that King Claudius goes to hell. In Hamlet's mind, it is not good enough to physically kill Claudius. Hamlet wants to make sure that Claudius's soul is damned for eternity. In Act Three, Scene 3, Hamlet has a chance to kill Claudius while he is praying. However, Hamlet refuses to kill Claudius and gives his explanation by saying,
"Now might I do it pat. Now he is a-praying. And now I’ll do ’t. And so he goes to heaven. And so am I revenged.—That would be scanned. A villain kills my father, and, for that, I, his sole son, do this same villain send to heaven. Oh, this is hire and salary, not revenge" (Shakespeare, 3.3.74-80).
Hamlet's hubris—his prideful desire to exact a revenge equal to the crime committed—prevents him from killing King Claudius at an opportune time. Hamlet's decision to let Claudius live leads to his tragic death. Claudius ends up poisoning the tip of Laertes's sword, which is used to kill Hamlet at the end of the play.