Lights-out manufacturing (also called a dark factory) is often considered the pinnacle of Industry 4.0. These are fully automated production facilities that operate without on-site human intervention. Integrating advanced robotics, IoT sensors, and AI-driven logistics eliminates the need for manual labor, heating, and lighting. 

This shift enhances precision, enables continuous operation, and significantly reduces costs. It marks a move from human-centric assembly to autonomous, self-optimizing cyber-physical systems.