The time spent updating documents is time well spent. During a development cycle, analysis focuses on what will be built in the current iteration. The conceptual model is enhanced to include more attributes and associations. The glossary is updated as necessary. Finally, system behavior is detailed by producing system sequence diagrams for critical or complex portions of the system.
Associations are the interesting and significant relationships between concepts.
For example, a typical system for a large company might include a relationship between departments and divisions. From the conceptual model point of view, only relationships that apply to a real-world understanding of the problem space should be included. Attributes are the logical data values of an object. In the conceptual model, only real-world attributes of the object should be documented. For example, a key attribute of a department is its name.