Harry Stimpson

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Harry Stimpson UX Designer

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Mountain Warehouse PDP Research

Turning the tables on the product display page

Following a redesign of a high-traffic product page, performance declined but the causes were unclear. I led a mixed-method research programme to understand user decision-making, identify barriers to confidence, and align stakeholders around evidence-based improvements. While rooted in e-commerce, this work focused on reducing user uncertainty, improving information clarity, and supporting better decisions challenges directly transferable to complex public service journeys.

Company

Mountain Warehouse

Platform

Mobile and Desktop Website

My role

UX Research

Timeline

2 months

Why this matters

Users navigating transport systems, like customers choosing products, must make decisions with incomplete information.

This project demonstrates my ability to:

Reduce decision friction in high-stakes journeys

Design for clarity, accessibility, and confidence

Align multiple stakeholders around user needs

Turn research into measurable service improvements

Problem

Users lacked confidence when making purchase decisions on the redesigned PDP. The experience did not effectively support users in, finding key information, interpreting product details and trusting their purchase decisions. This resulted in increased friction and potential loss in conversion.

My Role

Led end-to-end research strategy across multiple phases

Conducted qualitative and quantitative research

Defined success metrics across user and business needs

Influenced product direction through insight synthesis

Facilitated stakeholder alignment across teams

Embedded a test-and-learn culture through experimentation

Approach

Phase 1: Discovery & Alignment

Stakeholder Interviews & Assumption Unpacking (8 Participants)

Literature review

Competitive analysis

Remote card sorting (78 responses)

Data Analytics

Goal: Align on assumptions, understand business needs, and define how users expect information to be structured.


Phase 2: Behaviour & Usability

1-to-1 semi structured user interviews (5 participants)

Think-out-loud usability testing (7 participants)

Goal: Understand decision-making behaviour and identify friction in the current PDP experience.

Sample of affinity map

Three Key Insights

Across these phases, the research generated 20 distinct insights. From these, three key themes emerged that had the greatest impact on user decision-making and overall PDP performance. These insights highlight the primary barriers to purchase and informed the direction of design improvements.

Size & Fit Confidence is the Primary Barrier to Purchase

What we saw

Insight

Users lacked confidence in selecting the correct size. Especially new customers and in categories like women’s, kids, and footwear.


Impact
Hesitation to purchase or incorrect purchases → increased returns


Opportunity
Provide clearer, contextually relevant size guidance at the point of decision

Model Imagery is Critical for Assessing Fit and Driving Purchase Confidence

What we saw

Insight

Users depend on model imagery to assess fit, making it a critical factor in purchase confidence. Representation matters users are more confident when they can see products on models similar to themselves.


Impact
Lack of relatable imagery reduces confidence and conversion


Opportunity
Prioritise diverse, fit-focused imagery to help users visualise products

Lack Comparison Tools Forces Users into Workarounds

What we saw

Insight

The PDP does not adequately support product comparison, leading users to create their own workarounds. This indicates a clear unmet need for a more efficient and structured way to compare products.


Impact
Higher cognitive load, slower decisions, drop-offs


Opportunity
Introduce better comparison tools or streamline cross-product evaluation

Previous size guide design

Deep Dive: Improving Size & Fit Confidence

To address the lack of confidence in size selection, I tested iterative improvements to the size guide and selection experience using remote Figma prototype usability testing (46 participants).

Benchmark (current experience)

Task completion: 63%

Error rate: 3.4 per user

SEQ: 4.6/7

Iteration 1 - Improving clarity and relevance


What changed

Repositioned size guide CTA before the point of decision

Introduced gender and category-specific size guidance

Simplified table structure to improve readability (reducing need to scan across large matrices)


Outcome

Task completion: 84% (+21%)

Error rate: 2.3 per user (-1.1)

SEQ: 5.5/7 (+0.9)

Iteration 2 - Reducing complexity and cognitive load


What changed

Redesigned size guidance into a single, simplified one fold view

Introduced cm/inch toggle to support generational and geographical user preferences


Outcome

Task completion: 88% (+25%)

Error rate: 0.6 per user (-2.8)

SEQ: 6.1/7 (+1.5)

Through iterative testing, the size selection experience evolved from a complex, table-heavy interaction into a clearer, more accessible decision-making tool—directly improving user confidence and reducing friction at a critical point in the purchase journey

Improved size guide design

Impact

Business Impact (A/B Testing – 88,000 users)

+4.3% Add-to-Basket rate

+4.6% Revenue per Visitor

+9.22% engagement with size guidance

User Impact

Increased confidence in size selection

Reduced errors and backtracking

Faster, more confident decisions

Organisational Impact

Shift from assumption-led to insight-driven decisions

Alignment across product, design, and stakeholders

Established a test-and-learn experimentation culture

Outcomes

This research generated 20 validated insights that informed a structured experimentation pipeline.

This led to:

24 positive and 8 inconclusive A/B tests

Consistent improvements in conversion and engagement

A clearer understanding of key purchase drivers

What I Learned

This project shifted my focus from usability to confidence. Users often had the information they needed, but lacked the confidence to act on it.

I learned that small, well-timed improvements at key decision points can have a significant impact on both user experience and performance. Rather than aiming for a single “perfect” solution, iterative testing and validation proved far more effective in reducing uncertainty and improving outcomes.

It also reinforced the importance of early stakeholder alignment—ensuring insights are understood and actionable is key to turning research into real impact.

What I’d Do in a Transport Context

I’d apply the same research-led, iterative approach to help make journey planning and decision-making clearer, more accessible, and more reliable for a wide range of users.

In practice, that means:

Improving confidence in journey planning and ticket selection by ensuring users have the right information, at the right time, to make informed decisions without hesitation

Reducing friction across complex, multi-modal journeys by simplifying how users compare routes, modes, and options

Supporting users during disruption and uncertainty, where clear, timely, and trustworthy information becomes critical

Designing for accessibility from the outset, aligning with WCAG standards to ensure services are inclusive for all users

Using data and research to continuously measure and improve outcomes, focusing on real user behaviour and service performance

More broadly, I’m interested in how UX can help shape behaviour making sustainable choices like public transport, walking, and cycling feel easier, more intuitive, and more appealing through well-designed digital experiences.