What is the primary purpose of a User Story Card?

The primary purpose of a User Story Card is to provide a clear and concise description of a specific feature from the user's perspective, encapsulating the needs and requirements for that feature. A User Story focuses on who the user is, what they need, and why it’s important, facilitating better communication among team members as well as ensuring that development aligns with user needs. This format helps teams understand the functionality and context behind a requirement in a straightforward manner, which is crucial for designing user-centric features.

The other options focus on aspects that are broader or unrelated to the essence of a User Story. Detailed project plans, tracking milestones, and outlining project timelines pertain more to project management processes rather than the fundamental goal of capturing user requirements and facilitating user-focused development. By prioritizing user needs in a concise format, User Story Cards ensure that the development process remains agile and responsive to user feedback, which is vital in iterative development models.