How to Tackle Unexpected UI Risks with Five‑Question Method and Rapid Prototyping

Introduction

Any complex software project inevitably encounters unknown risks during development. The PMBOK guide classifies risks as known‑known, known‑unknown, and unknown‑unknown. Understanding these categories helps interaction designers respond to unexpected requirements.

Project Background

A banking client added a new requirement for guarantee deposit accounts mid‑project, describing a need to query all active accounts, including balances and transaction details. The interaction designer had to interpret this brief description without direct client clarification.

1. Identify the Real Problem

During testing, developers noticed a discrepancy: the main account displayed a balance that did not match the sum of its sub‑accounts. This revealed that the main account’s balance should be shown independently, with its own query and transaction entry.

2. Ask About Solution Ideas

The designer asks the stakeholder for their preferred solution, then aligns it with the discovered issue. If the stakeholder lacks an idea, the designer proceeds to the next step.

3. Quickly Sketch Your Idea

Recognizing that the interface lacks a main‑account balance display, the designer quickly drafts a revised layout, annotates it, and shares it for alignment.

4. Iterate Until Consensus

Developers raised two concerns: (1) the concept of a total balance for main/sub‑accounts no longer applies, and (2) they prefer the balance and transaction buttons placed below the sub‑account cards. The designer accepts the factual change and negotiates button placement, adding clear labels such as “Main Account Balance Query”.

5. Report and Confirm Final Solution

The designer escalates the decision to the project manager, who coordinates with the client to avoid contradictions. Reporting through the manager ensures that any technical constraints are communicated and documented.

6. Update Files and Communicate Changes

After consensus, the interaction designer updates the prototype, records change logs, and distributes the revised designs to the team, ensuring consistency across related pages.

7. Follow Up Implementation

Post‑development, the designer verifies the implementation, reports any residual UX issues, and updates the verification checklist if needed.

8. Retrospective

A quick retrospective highlights that the hidden risk stemmed from assumptions about balance aggregation, insufficient detail review, and incomplete business understanding. Recognizing these root causes helps prevent similar unknown risks.

Conclusion

This case demonstrates how systematic questioning, rapid prototyping, and structured communication enable interaction designers to navigate unknown risks, align stakeholders, and deliver reliable frontend solutions.