What is the significance of having a lifeguard on duty at all times?

Having a lifeguard on duty at all times is crucial because it ensures constant supervision and the ability for immediate response to any emergencies that may arise. Lifeguards are trained to monitor swimmers, assess potential hazards, and react quickly to prevent drowning or injuries. Their presence helps to identify risky behaviors and maintain a safe environment, providing peace of mind for both swimmers and parents. This authoritative figure plays a vital role in emergency situations, as they are equipped with the skills and knowledge necessary to perform rescues and administer first aid if needed.

The other choices do not address the primary purpose of a lifeguard's role, which revolves around safety and emergency response rather than facilitating lessons, enhancing aesthetics, or managing pool entry fees.