Improving Inventory Visibility: Testing UX Solutions for Out-of-Stock product
Background
Role: Lead UX Researcher
Timeframe: 2 months
Team: Product Manager, Designer, Developers
Overview:
This research was built upon insights from a foundational study that uncovered major pain points in the online shopping experience. One of the most pressing frustrations identified was the inability to find desired products in stock—particularly in the user’s preferred size. This recurring issue not only disrupts the shopping journey but also leads to frustration, decreased engagement, and, ultimately, lost sales.
Problem Statement:
When users encounter an out-of-stock item in their preferred size, they are often left with limited options: abandon their search, browse aimlessly for alternatives, or leave the platform altogether. This friction in the shopping experience can erode customer trust and loyalty. The challenge for the retailer was to explore UX-driven solutions that could minimize frustration, guide users toward alternative choices, and improve overall satisfaction.
Research Objectives:
The primary objectives of this study were to:
Understand user expectations when faced with an out-of-stock product in their preferred size.
Evaluate the effectiveness of three proposed UX solutions in reducing frustration and improving engagement:
Streamlined size filtering on the search grid to help users quickly find in-stock items.
Prompting users to save their size preferences on the product detail page (PDP) for personalized recommendations.
Recommending similar in-stock products based on the user’s saved size preferences.
Identify the optimal solution(s) that would create a more seamless and satisfying shopping experience.
By addressing this issue through research-backed UX enhancements, the goal was to create a more intuitive shopping journey that keeps users engaged and improves conversion rates.
Effective Stakeholder Communication & Research Process
1. Research Request & Alignment
The research process begins when I receive a request from a stakeholder, often a Product Manager (PM), Designer, or other key collaborator. Instead of immediately drafting a test plan, I first set up a meeting with the PM to align on the core business problem driving the request. This discussion helps uncover the "why" behind the research, ensuring that we are solving a real user problem rather than just validating an assumption. By digging deeper, I often refine the request to better address the user’s needs while also aligning with business objectives.
Key questions I ask during this phase:
What assumptions exist about the problem?
Who are the users in this project?
How does this project align with company/business goals?
What research / knowledge do you already possess on this topic?
What are the success metrics or key outcomes?
Are there any known constraints or business considerations?
This collaborative discussion allows me to move forward with clarity, ensuring that the research effort is both impactful and aligned with business goals.
2. Determining Methodology & Developing the Test Plan
Once the research objectives are clear, I draft a test plan that outlines the methodology, participant criteria, and research script. I meet with relevant stakeholders—including PMs, Designers, and sometimes Engineers—to review the test plan and determine whether the chosen approach is the best fit for the problem.
In this stage, I consider:
Methodology selection: Does this require qualitative insights (e.g., moderated usability tests, interviews) or quantitative validation (e.g., surveys, A/B testing)?
Script refinement: Are the questions structured to avoid bias and extract meaningful insights?
Participant criteria: Are we targeting the right users for the study?
By involving stakeholders early in the test plan review, I ensure buy-in from the team, reducing the risk of misalignment later on. This collaborative approach also helps teams feel more invested in the research process.
3. Research Execution & Delivering Actionable Insights
Once the study is completed, I synthesize the findings into clear, actionable insights. Rather than delivering a one-size-fits-all report, I tailor my deliverables based on stakeholder needs.
I provide insights in one of the following formats:
Detailed reports for teams that prefer in-depth documentation.
Concise decks with high-level takeaways for leadership or fast-moving teams.
Live walkthroughs or workshops to engage teams and facilitate discussion.
In my final share-out, I go beyond just presenting findings—I tie insights back to business goals, offering clear recommendations that help drive decision-making. Additionally, I ensure that leadership is aligned by summarizing key insights in executive-friendly formats, highlighting critical impact areas.
By structuring my research process in this way, I ensure that my work not only provides valuable user insights but also directly informs strategic business decisions.
Research Plan
Methods & Tools
Moderated user interviews were chosen as the primary research method to assess and refine three design concepts. This method allowed for real-time observation of user interactions, providing rich, qualitative feedback on usability, pain points, and preferences.
Key aspects of the research process included:
Conducting remote interviews using UserZoom on three mobile web prototypes.
Engaging six participants, selected based on demographic and behavioral criteria aligned with the retailers target shoppers.
Exploring users’ thought processes through open-ended tasks and follow-up questions to uncover nuanced insights.
Sample Task Script
This study used a within-subject design with counterbalancing to minimize bias and order effects. The three prototypes were presented in a randomized order to ensure that participant responses were not influenced by the sequence in which the prototypes were shown.
Participants were guided through a series of tasks and follow-up questions, including:
Task Example:
You’ve landed on this category page. Take a moment to explore the content. As you navigate, share your initial impressions—what stands out to you, and what feels clear or confusing?Prompts:
Understanding and Intent:
What does ‘All Sizes’ mean to you?
Would you feel inclined to select it? Why or why not?
What outcome would you expect if you selected it?
Interaction and Usability:
Go ahead and interact with the feature. As you do, please share your thoughts aloud—what feels intuitive or unexpected?
How easy or difficult was it to understand the interaction?
Information and Clarity:
How clear is the information displayed?
Do you find it helpful or relevant? Why or why not?
Is there any information missing that you would expect to see?
Editing and Control:
How would you remove or modify these selections?
Does the process feel intuitive? Why or why not?
Preference and Feedback:
What do you like or dislike about this feature?
If you could improve one thing about this feature, what would it be?
How would you rate the usefulness of this feature on a scale of 1 to 5 (1 = not at all useful, 5 = extremely useful)?
Are there any other suggestions or improvements you’d recommend?
This script ensured consistency across sessions while providing flexibility to delve deeper into user feedback.
While I rely on a structured script to ensure consistency across user interviews, I also allow room for flexibility. After the first few sessions, unexpected user pain points may emerge—ones I hadn’t initially anticipated. To uncover the ‘why’ behind these issues, I adapt my questioning in real time, diving deeper into relevant topics as they arise. This curiosity-driven approach helps me gain a richer understanding of user needs, ensuring that my research captures not just what users do, but why they do it.
Process & Findings
Process
Note-taking during sessions: Captured key themes, user quotes, and non-verbal cues.
Familiarization: Reviewed transcripts multiple times to identify overarching patterns.
Initial coding: Highlighted notable points without categorization.
Thematic grouping: Organized findings into broader categories (e.g., frustrations, motivations).
Actionable insights: Synthesized themes into clear recommendations tied to user experience.
Baymard Institute guidelines were referenced where applicable to validate findings and align with best practices.
Key Findings and Recommendations
1. Stock Availability and Notifications
Recommendation:
Provide more detailed information on product pages regarding stock status, including whether an item is permanently out of stock or expected to be restocked soon.
Offer an option to notify users of similar products if the original item is not expected to return.
Supporting Insights:
Participants expressed frustration when back-in-stock notifications were unreliable or when items never returned.
Improving the reliability and functionality of back-in-stock notifications would enhance user confidence and increase conversion rates.
Relevant User Quote: “I wish it would tell me if it’s out of stock forever or if it’s coming back. If I don’t know, I won’t check back.”
2. Size Selection and Display
Recommendation:
Allow users to select multiple sizes to avoid limiting the number of products displayed, which could cause users to leave the site prematurely.
Display products that are unavailable in a user’s selected size on the search grid, as participants still want to see all available products.
Supporting Insights:
Many participants noted that sizing can vary even within the same brand, making reviews and size/fit information critical for decision-making.
Participants mentioned that depending on the product's fit, they might size up or down (e.g., preferring a looser or tighter fit).
Relevant User Quote: “I want to filter by size but not be restricted—sometimes I size up or down depending on the fit.”
3. Size Preference and Personalization
Recommendation:
Provide an opt-in feature for users to save size preferences and allow them to easily toggle this feature on or off.
Enable users to create multiple size profiles for different individuals they may shop for.
Save a user’s size selection for the duration of the shopping journey without requiring them to log in or create an account.
Supporting Insights:
Some participants appreciated the idea of a "My Saves" feature to streamline shopping but were concerned about it being too restrictive.
Participants assumed they would be redirected to a login page if they selected "Yes, Add to My Sizes," which they felt would interrupt their shopping flow.
Relevant User Quote: “It would be nice to save sizes for myself and others I shop for, like my kids.”
4. Search and Filtering Experience
Recommendation:
Introduce an AI-driven suggestion model to help users quickly find relevant filters based on their shopping behavior.
Add an auto-complete feature in the search box to suggest search terms and account for misspellings.
Supporting Insights:
Participants found the ability to browse similar items in stock to be highly valuable but were unsure how to use the "something else" text box effectively.
Participants often didn’t know what product attributes to search for and were concerned about getting inaccurate results due to spelling errors.
Impact & Outcome
Collaborating closely with designers, product managers, and stakeholders, I delivered actionable insights that directly informed design iterations. This user-centered approach ensured that key pain points were addressed early, optimizing the overall product experience.
Notable outcomes include:
Improved Product Discoverability: Introducing detailed stock status and reliable back-in-stock notifications reduced user frustration and increased confidence in purchasing decisions.
Optimized Search Functionality: AI-driven search suggestions and auto-complete functionality improved search accuracy and helped users find relevant products faster, increasing search-to-purchase conversion rates.
Cross-Functional Alignment: Research insights fostered strong collaboration across design, product, and engineering teams, ensuring a cohesive strategy and alignment throughout the design process.
Continued Iteration: Follow-up testing helped refine the final design, resulting in a product that more effectively meets user needs and expectations, ensuring that user feedback was seamlessly integrated into the final solution.
By grounding the design process in robust research, we successfully mitigated a critical pain point for users, delivering a more seamless and satisfying shopping experience.