The name of this model for communication is a bit misleading. Nonviolent communication is a communication process developed by Marshall Rosenberg beginning in the 1960s. It focuses on three aspects of communication: self-empathy (defined as a deep and compassionate awareness of one's own inner experience), empathy (defined as listening to another with deep compassion), and honest self-expression (defined as expressing oneself authentically in a way that is likely to inspire compassion in others).
NVC is based on the idea that all human beings have the capacity for compassion.
Have a read of Chapter One from "Nonviolent Communication: a language of compassion" by Marshall B. Rosenberg, Ph.D.
Chapter One: Giving from the Heart, the Heart of Nonviolent Communication
“What I want in my life is compassion, a flow between myself and others based on a mutual giving from the heart.”
—Marshall B. Rosenberg