Why are submarines robots more practical for deep ocean research than submersibles designed to carry people are?

Submarine robots, or autonomous underwater vehicles (AUVs), are more practical for deep ocean research because they can operate at greater depths and endure extreme pressures without the need for life support systems. They can be deployed for extended periods, covering larger areas and collecting data in environments that are too hazardous for human divers or piloted submersibles. Additionally, these robots can be equipped with advanced sensors and cameras, allowing for detailed exploration and data collection while reducing operational costs and risks associated with human missions.