SYSE.26:4.5 - Exercise the interaction before relying on it

Try the supported case with a representative user and the intended result consumer. Include one valid variation, one invalid or unsupported request, one delayed attempt and one interrupted operation whose effect may already have occurred. Check that each leaves an intelligible next move and preserves the result’s identity.

A desk walkthrough tests the description. A trial against the actual provision tests more: whether the request reaches the right System, the operation works under the stated conditions and the result can be used. Keep those evidence claims separate. SYSE.12 distinguishes a readiness assessment made before relying work from a later assessment of actual use; SYSE.36 helps observe software-service user tasks. Stop at the design result or bounded trial result that the current decision needs.