A user requirements document, written by the product manager, is centered around the end user’s needs and expectations for a product.it translates user requirements into. [provide a list of contractual or task level assumptions and/or constraints that are preconditions to preparation of the frd. They communicate what problem needs. Business requirements documents (brds) center on strategic objectives, business processes and user needs at a high level. If you are unfamiliar with this document, do not be vexed.