Here's why:
* Hamlet contemplates suicide, yet he is deeply afraid of death. He describes death as "the undiscovered country from whose bourn no traveler returns," implying he is afraid of the unknown. This creates irony because he is considering ending his life, yet fears what lies beyond it.
* He speaks of the "slings and arrows of outrageous fortune," which seem like a reference to the pain and suffering he is enduring. However, Hamlet's own inaction and indecision are also contributing to his suffering. He is a victim of his own inability to act.
* He imagines death as a "sleep," implying that it is a restful and peaceful state. But in reality, Hamlet is deeply troubled and his inability to act leads to a great deal of mental and emotional anguish.
The entire soliloquy is filled with this kind of dramatic irony, where Hamlet's words contrast with the reality of his situation, creating a sense of tension and complexity.
This is just one example, and there are many other instances of irony throughout the play. Hamlet is a master of irony, and his use of it helps to explore the themes of deception, revenge, and the human condition.