When are detective controls most valuable?

Detective controls are most valuable when preventive controls fail because they are designed to identify and alert stakeholders to security incidents that have already occurred. These controls do not stop incidents from happening but instead provide essential information about breaches or policy violations that may have slipped through preventive measures.

When preventive controls, like firewalls or access controls, are functioning effectively, the likelihood of incidents is reduced, but the role of detective controls becomes crucial when those preventive measures are compromised. They offer a means to detect breaches, assess the impact, initiate a response, and provide insights for improving security measures in the future.

In contrast, during the planning phase of a network, the emphasis is on establishing preventive controls to ensure security from the start. Similarly, when building a new network, the focus remains on prevention rather than detection. Thus, it is in situations where preventive measures have not functioned as intended that the value of detective controls becomes apparent, allowing organizations to respond to threats more effectively.