Which of the following is NOT a characteristic of a professional lifeguard?

A professional lifeguard is characterized by qualities that ensure the safety and well-being of those they supervise. Being consistent is crucial; it means that a lifeguard follows protocols and maintains a high level of vigilance at all times. Reliability is equally important, as lifeguards must be trusted to respond quickly and effectively in emergencies. Courteousness reflects the ability to interact positively with patrons, creating a welcoming environment while still maintaining authority.

In contrast, immaturity is not a trait that contributes to the effectiveness or professionalism of a lifeguard. It can lead to poor decision-making, lack of focus, and an inability to handle stressful situations, all of which are critical for the safety of swimmers and beachgoers. Thus, being immature would undermine the responsibilities and expectations placed on a professional lifeguard, making it the correct answer for what is NOT a characteristic of a professional lifeguard.