To identify underlying causes, the analyst needs a technique that helps them explore what is happening in practice and uncover where breakdowns or inefficiencies might be occurring. The documentation describes scenario analysis as “telling the story of a task or transaction,” and explains it is useful when analysing or redesigning processes because it helps staff and analysts work through the steps required, visualise them clearly, and understand what triggers the work and what actions must be completed to achieve a successful outcome.

In a retail setting, declining sales can result from failures or friction in key customer-facing scenarios (e.g., browsing, ordering, returns, stock availability, customer service escalation). By building and walking through scenarios end-to-end, the analyst can pinpoint where delays, handoffs, rework, unclear decision points, or system constraints occur—each of which can contribute to poorer customer outcomes and, ultimately, sales decline. Scenario work also creates a concrete basis for validating hypotheses with stakeholders and for identifying what evidence and data should be gathered next.

The other options are less directly “cause-finding” for the stated problem. A customer journey map focuses on experience and touchpoints (useful, but it may not expose operational root causes in enough detail). Use case diagrams define system interactions for requirements, not root cause diagnosis. A business activity model gives a conceptual “what activities exist” overview; it is valuable for gaps, but scenario analysis is the technique explicitly positioned to walk through transactions to reveal where problems arise.