Within the ITIL framework, maintainability is a key component of Availability Management and refers to the ability to restore a service or component to operational status. This process involves a lifecycle of both proactive and reactive activities. The stages are:

1. Anticipation of Failures: Proactive measures, such as risk analysis and predictive monitoring, to prevent failures or prepare for rapid recovery.

2. Detection of Failures: Reactive monitoring and alerting to identify that a failure has occurred as quickly as possible.

3. Restoration of the Data and IT Service: The set of reactive activities, including diagnosis and repair, to bring the service back to its operational state, minimizing downtime.

A. COST OF FAILURES: This is a metric used in Business Impact Analysis (BIA) to quantify the financial impact of downtime, not a stage in the technical restoration process.

E. EFFECT OF FAILURES ON SERVICE LEVEL AGREEMENTS: This is an outcome or a measure of the impact of a failure on service delivery commitments, not a step in the maintenance activity itself.

1. ITIL® Service Design (2011 Edition), AXELOS Global Best Practice.

Section 4.4.4, "Availability management concepts," and 4.4.5, "Activities, methods and techniques": This chapter distinguishes between proactive and reactive activities. Proactive activities (p. 88) include risk assessment and preventative actions, which corresponds to Anticipation. Reactive activities (p. 88) are triggered by failures and include monitoring, detection, diagnosis, and restoration, which directly support Detection and Restoration.

2. Foundations of IT Service Management: Based on ITIL V3, by Jan van Bon, et al.

Chapter 6, "Availability Management": The text describes the process of ensuring service availability through proactive measures (e.g., designing for reliability, preventative maintenance) and reactive measures (e.g., rapid detection and recovery from incidents). This model directly aligns with the concepts of anticipating, detecting, and restoring service.

3. University of Washington, "ITIL V3 Foundation Courseware."

Module on Service Design, Availability Management: University course materials on ITIL consistently teach that Availability Management is composed of proactive and reactive elements. Proactive work aims to prevent failures (Anticipation), while reactive work focuses on responding to failures, which begins with Detection and concludes with Restoration.