Test tasks are assigned to testers to develop and run tests against scenarios. The purpose of testing a scenario is to validate that the product implements the scenario as expected by the user. Validating that a build reflects the functionality envisioned in the scenario requires an understanding of the scenario and its boundary conditions. Validation tests must be written to cover the complete functionality and the boundary conditions of the scenario. Validation tests are run until none are blocked. Bugs are created to report any problems uncovered through testing.