Here's why:
* Definition: A soliloquy is a dramatic speech delivered by a single character, expressing their thoughts and feelings aloud, often when alone on stage.
* Purpose: Soliloquies are used to reveal a character's inner world, motivations, and plans to the audience.
* Dramatic effect: Having only one character on stage creates intimacy and allows the audience to fully focus on the character's thoughts and emotions.
While there are rare exceptions, the essence of a soliloquy is the isolation and introspection of a single character speaking their mind.