BDD Test Cases from User Stories: 5 Steps and 12 Scenarios

User stories set the destination. Test cases map every path, including the wrong ones. In this post we walk through a 5-step BDD decomposition framework for turning a single user story into concrete Given/When/Then scenarios, with a complete worked coupon example. BDD (Behavior-Driven Development) structures tests as Given/When/Then scenarios that both stakeholders and tools like Cucumber or SpecFlow can understand. Most teams write user stories in a format like: As a checkout user, I want to apply a discount coupon, So that I pay less for my order. Then they try to extract test cases directly from that sentence. The result is a handful of happy path scenarios and a nagging sense that something important was missed. That instinct is right. This post explains why, and what to do about it. Why User Stories Fail as Test Case Sources User stories describe intent, not behavior. They answer why a feature exists, not what the system should do in every situation. The coupon story above doesn't