Requirements are maintained to ensure that requirement accuracy is retained and there is consistency throughout the requirements life cycle. It also supports the reuse of the requirements in other solutions.
To ensure that the requirements remain relevant to the solution it must be maintained over time. But in order to do this, the requirements must be consistently represented, reviewed, approved and easily accessible.
There are some elements that can help with the maintaining requirements and they are:
1. Maintain requirements: the business analyst is responsible for maintaining requirements to ensure that they remain correct and current.
To maintain these requirements they should be named, defined and easily accessible to the stakeholders.
2. Maintain attributes: when a business analyst is eliciting requirements they also elicit the attributes of those requirements.
Attributes are information about the requirements such as the priority, source and complexity which help with managing these requirements. An attribute can change throughout the life cycle of a requirement.
3. Reusing requirements: in certain situations requirements can be reused. All requirements should be identified, named, defined and stored in an easily retrievable manner.
This would help with maintaining the requirements for reuse.
Requirements can be reused in the current solution, similar solutions, similar departments and throughout the organization.
But this is all based on the level of abstraction of these requirements, requirements that are not specific to that solution are easier to reuse then specific requirements.