Ace the ITIL 4 Foundation Exam 2026 – Level Up Your IT Skills with Confidence!

Availability in IT service management primarily refers to the ability of a service to perform its agreed functions when required. It encompasses the uptime and readiness of a service to be operational during the times it is needed by users or other systems. This concept goes beyond just having the service up and running; it also involves ensuring that the service meets the predefined criteria for functioning, as outlined in service-level agreements (SLAs) between service providers and customers.

The focus on agreed functions indicates that availability is about meeting specific expectations set forth at the outset, ensuring that users can rely on the IT services when needed. This is essential for maintaining business operations, where any downtime can lead to significant disruptions and impact overall performance.

In contrast, the other options, while they may relate to aspects of service management, do not encompass the complete definition of availability. Performance during peak hours, customer satisfaction, and resource efficiency are important metrics and are interconnected with availability, but they do not specifically define it. Availability centers on the service's capability to be operational and fulfill its intended role when it is called upon. Thus, option B clearly represents the core principle of availability in the context of IT service management.