How can you ensure requirements are complete but not over-specified?

3 Avoid unnecessary details and assumptions

A common mistake when writing requirements is to include too many details or assumptions that are not relevant, essential, or agreed upon by the stakeholders. This can lead to over-specification, which can limit the flexibility, creativity, and innovation of the design and development team, and cause conflicts, changes, or delays in the project. To avoid over-specification, you should focus on the what and why of the requirements, rather than the how and when. You should also avoid using vague or subjective terms, such as "user-friendly", "fast", or "high-quality", and instead use clear and objective criteria, such as "the system should respond within 3 seconds", or "the system should have a 99.9% uptime".

4 Use models and diagrams

A picture is worth a thousand words, especially when it comes to requirements. Using models and diagrams can help you ensure that your requirements are complete but not over-specified, as they can provide a visual representation of the system structure, behavior, and interactions. Models and diagrams can also help you communicate your requirements more effectively and efficiently to different stakeholders, as they can reduce ambiguity, confusion, and misinterpretation. Some examples of models and diagrams that you can use for your requirements are entity-relationship diagrams, data flow diagrams, state transition diagrams, or sequence diagrams.

5 Review and refine your requirements

Finally, you should review and refine your requirements regularly throughout the project lifecycle, as they are not static, but dynamic and evolving. Reviewing and refining your requirements can help you ensure that they are complete but not over-specified, as they can reflect the changes, feedback, and lessons learned from the project environment, stakeholders, and deliverables. You should also prioritize your requirements based on their importance, urgency, and dependency, and manage their scope, quality, and risks accordingly. You can use tools such as a requirements traceability matrix, a requirements management software, or a version control system to help you review and refine your requirements effectively and efficiently.