Happy Path

The happy path represents the best-case scenario for any feature. For a signup form, the happy path is: user enters a valid name, a valid email, a strong password, clicks submit, and successfully creates an account. Testing the happy path confirms that the core functionality works under ideal conditions.

The danger of testing only the happy path is that it creates a false sense of confidence. An application that works perfectly on the happy path can still fail catastrophically when users deviate even slightly. Real users mistype, click the wrong buttons, use unexpected browsers, lose internet connectivity mid-action, and do countless other things the happy path does not cover.

Vibecoded applications often work well on the happy path because that is what the AI optimized for based on the prompt. The real quality of an application is revealed when testing moves beyond the happy path into error handling, edge cases, and adverse conditions. Professional QA testers spend the majority of their time in these off-happy-path scenarios.