What is the main purpose of surveillance in security?

The main purpose of surveillance in security is to monitor activities and deter criminal behavior. This function serves as a proactive strategy aimed at preventing incidents before they occur. By keeping a watchful eye on premises, security personnel can identify suspicious activities or behaviors that may indicate potential threats. The visible presence of surveillance methods, like cameras or patrols, can act as a deterrent to criminals, as they are less likely to engage in illegal activities when they know they are being watched.

While the other options relate to important functions of security, they are more specific applications or outcomes of surveillance rather than its primary purpose. Collecting evidence for prosecution is an essential task of security but typically comes after an incident has occurred, rather than focusing on prevention. Facilitating crowd control is particularly relevant in certain contexts, such as events, but does not encompass the overall intent of surveillance. Ensuring compliance with legal protocols is crucial for security operations but is more about operational guideline adherence than the fundamental objective of surveillance itself.

Thus, the main purpose of surveillance lies in its role as a preventive measure designed to monitor and deter undesirable behavior, making it central to effective security strategies.