The reader would get a better idea of how the main character's actions look to another character. it has the biggest impact if it where told from another perspective.
Figurative language is poetic language that is not literal.
You might do something you never wanted to do in the first place, without thinking about it. For example, if you were startled by someone sneaking up on you, and you punched them in the face impulsively, and that person was, say, your mother, then you might want to undo your actions.
A poem is subjective since each reader will have a personal reaction to the poem. It is because the poem is drawn from thoughts and feelings that can change from person to person.