LEARN. PRACTICE. GROW.Concept and mechanism
A model helps answer a question that isolated prose makes difficult. A flow with responsibilities shows handoffs between teams; a data model clarifies concepts and relationships; a decision table exposes combinations of conditions; a state model shows allowed transitions. Select the representation for the uncertainty being resolved and explain the notation to participants. No diagram makes its assumptions true by itself. In a file-receipt process, distinguish received, validated, rejected, and consumed. The same word processed may hide different states for APS and business. Also define exceptions such as repetition, correction, missing data, timeout, and cancellation when they belong within scope.
Guided application
In an exercise, one rule says amounts up to 1000 receive automatic approval and another says amounts from 1000 require review. The exact value 1000 satisfies both. Do not choose whichever rule appears first without an explicit policy: present the overlap to the owner and add boundary examples. In another exercise, each file contains multiple lines, but the model links a transaction directly to the file without identifying its line. This can prevent distinguishing two transactions in the same file. Check consistency among prose, models, and acceptance criteria. A performance requirement needs an operation, population or load, threshold, and measurement method; fast is insufficient. Verification seeks these quality defects before they become incompatible implementation interpretations.
A boundary case exposes an overlap that two normal examples can hide.
Common pitfalls
Diagram treated as proof; happy path without exceptions; vague requirements treated as testable.
Related topics: Plan analysis and decisions · Elicitation, evidence, and collaboration · Life cycle, priorities, and changes
Model the uncertainty and verify the set for consistency.
Reference: Requirements documenting · Six-knowledge-area blueprint / handbook May 2026