The Three Types of Requirements on Any Project

In discussing requirements on any project, it’s important to realize there are really three different types of requirements.
First are the known requirements. These are the requirements users tell us about. Analysts have honed good techniques over the years for gathering a project’s known requirements: interviews, story-writing workshops, open-ended questions, and more.
But we’re fallible. We don’t always ask all the right questions. And users sometimes don’t think of everything. Maybe a user interview was cut short, or a user was absent from a story-writing workshop.
Those requirements that don’t come up when we talk to users are a project’s overlooked requirements. They’re just as important as the known requirements, but we somehow miss them, don’t hear them, or the stakeholders never mention them.

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