Proper deployment and configuration of defense in depth products, data and user access controls, patch management and more are fundamental to effective IT security. But active and continuous monitoring of those solutions, the traffic running through them, and the logs and alerts they generate are just as important.
Seems obvious. But, 24×7 monitoring can be labor intensive, tedious, and prone to error. If your environment is not properly instrumented, staffed, and operating with best practice processes, you may be wasting time on false positives, or missing early indicators of an attack in progress.
Attack surface understanding, infrastructure monitoring, and threat awareness are complex efforts. Why not trust it to specialists who do it day in and day out?