Which metric is commonly used to measure the speed of detecting cybersecurity incidents?

• A. Mean time to respond
• B. Mean time to recover
• C. Mean time to detect
• D. Incident closure rate

Answer: (C)

Detecting incidents quickly is all about measuring how fast you become aware of a breach or attack. The mean time to detect captures the average time from when an incident starts to when the security team first detects it. This directly reflects the effectiveness of your monitoring, alerting, and threat-hunting capabilities, so a lower value means you’re spotting problems faster and reducing dwell time for attackers. Other metrics focus on what happens after detection or after detection is acknowledged: responding quickly after detection, recovering services, or simply closing incidents. Those are important for containment and restoration, but they don’t measure how fast detection itself occurs. Incident closure rate measures how many incidents you finish in a period, which is a throughput metric and not about detection speed. So the best metric for the speed of detecting cybersecurity incidents is the mean time to detect.