Which of the following is the BEST key performance indicator (KPI) to measure the ability...

Mean time between failures (MTBF) is a key performance indicator (KPI) that measures the average time that a system or component operates without interruption or failure. MTBF is a common metric for reliability and availability of IT services. A higher MTBF indicates a lower frequency of failures and a higher ability to deliver uninterrupted IT services. According to the CRISC Review Manual 2022, MTBF is one of the KPIs for IT service delivery1. According to the CRISC Review Questions, Answers & Explanations Manual 2022, MTBF is the correct answer to this question2.

Mean time to recover (MTTR), planned downtime, and unplanned downtime are not the best KPIs to measure the ability to deliver uninterrupted IT services. MTTR measures the average time that it takes to restore a system or component to normal operation after a failure. Planned downtime measures the scheduled time that a system or component is not available for use due to maintenance or upgrades. Unplanned downtime measures the unscheduled time that a system or component is not available for use due to failures or incidents. These KPIs are useful for measuring the impact and duration of service interruptions, but they do not directly reflect the ability to prevent or avoid service interruptions.