The purpose of a Definition of Done (DoD) in Agile development is to ensure that each user story is complete and meets the team's quality standards. The DoD is a shared understanding among the development team of the criteria that must be met before a user story can be considered "done" and ready for release.
The DoD typically includes a set of requirements or criteria that must be met for each user story, such as code quality standards, testing requirements, documentation, and acceptance criteria. By establishing a DoD, the team ensures that each user story is complete and meets the team's quality standards before it is considered "done." The DoD is an important component of the Agile development process, as it helps to ensure that the product is of high quality and meets the needs of the stakeholders. It also helps to prevent misunderstandings and ambiguity regarding when a user story is complete, which can lead to delays or rework. The DoD is typically reviewed and updated during the Sprint Retrospective to reflect any changes in the team's processes or standards.