Design a feature to reduce food waste for a grocery delivery app

Design Challenge Double Diamond: Discover → Define → Develop → Deliver

What They’re Really Asking

Can you tackle a complex, behavior-driven problem with a measurable, user-centered design solution?

Framework: Use the Double Diamond: Discover → Define → Develop → Deliver framework to structure your answer.

Strong Sample Answer

I would lead with the Double Diamond framework to tackle food waste. In the Discover phase, I'd conduct user interviews and diary studies with 20 households to uncover pain points like overbuying and poor meal planning. Using Figma for rapid prototyping, I'd map the current user journey to identify waste moments. In Define, I'd synthesize insights into a problem statement: 'Users need a way to match purchases with exact consumption needs.' I'd develop a 'Smart Cart' feature integrating inventory tracking via barcode scanning, AI meal suggestions based on what's expiring, and a 'Leftover Challenge' gamification layer. I'd run usability tests with 15 users using UserTesting, iterating on wireframes to reduce cognitive load. In Deliver, I'd measure success via reduction in reported food waste (target 30%) and increased user engagement (target 20% weekly active usage). I'd present a high-fidelity prototype in Figma, sharing results with cross-functional teams, using A/B testing to validate the feature's impact on order accuracy and waste reduction.

Common Mistake to Avoid

Don’t do this: Many candidates propose a complex solution without first validating assumptions through user research or defining measurable metrics for success.

Company-Specific Variants

Google Variant

At Google, emphasize data-driven decision making—show how you'd use Google Analytics or internal tools to measure feature adoption and waste reduction impact.

Apple Variant

At Apple, focus on intuitive, frictionless interfaces—keep the feature minimal and delightful, leveraging on-device intelligence to respect user privacy.

Meta Variant

At Meta, prioritize social dynamics—frame the solution as a community challenge where users share waste-saving tips and earn badges for reducing food waste.

📚 Recommended Resource

The 0-1 PM Interview Playbook (2026 Edition)

Product design thinking and UX interview frameworks used at Google, Apple, and Meta.

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