According to the Business Analysis Body of Knowledge (BABOK), the concept of maintaining requirements is centered on the need for accuracy, consistency, and the potential for reuse of requirements across different projects and solutions.
Purpose: The main purpose of maintaining requirements is to ensure their accuracy and consistency throughout the entire requirements life cycle, and to support reuse of requirements in other solutions.
Types of Requirements: This includes goals, objectives, business requirements, stakeholder requirements, solution requirements, and transition requirements. These should be maintained throughout their life cycle according to BABOK guidelines.
Designs: BABOK also suggests maintaining designs throughout their life cycle, as needed.
Maintain Requirements: In line with BABOK, requirements should be kept current and correct even after an approved change. They should be clearly named, defined, and easily accessible to stakeholders.
Maintain Attributes: According to BABOK, an attribute may change even though the requirement does not.
Reusing Requirements: BABOK encourages identifying requirements that are suitable for long-term use by the organization. These should be clearly named, defined, and stored in a way that makes them easily retrievable.
Requirements (maintained): Defined once, these requirements are available for long-term usage by the organization. They may become organizational process assets or be used in future initiatives. In some cases, a requirement that was not approved or implemented may be maintained for a possible future initiative, as suggested by BABOK.
Designs (maintained): According to BABOK, designs may be reusable once defined. For example, as a self-contained component that can be made available for possible future use.