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Google·Product Manager·Onsite - Product Sense / Strategy·Senior

Senior
Apr 2026

Summary

PM interview at Google, one question about picking a north star metric for Google Photos. Pretty lean on details but it's the kind of question that sounds straightforward until you're actually in it.

Questions Asked (1)

Q1

What should be the north star metric for Google Photos?

Product Analytics & MetricsProduct StrategyProduct Sense & Ideation
Author's notes

I went straight for DAU and the interviewer kind of just waited.

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AI HintsAI Generated

Suggested Approach

Start by clarifying Google Photos' mission and core value proposition, then define a north star metric that captures the essence of user value and aligns with business goals. Evaluate potential metrics against criteria like actionability, leading indicator, and alignment with long-term vision, and finally recommend one with justification.

Pro tip: Acknowledge that the north star metric may evolve as the product matures, but for now, focus on a metric that balances user engagement and retention, such as 'weekly active users who view or share memories'.

1. Clarify Product Mission and Goals

Restate Google Photos' mission to organize, store, and share memories effortlessly, and identify key business objectives like user growth, engagement, and monetization.

2. Identify Core User Value

Determine what makes Google Photos valuable to users: seamless backup, intelligent organization, and easy sharing of memories. The north star should reflect this value.

3. Brainstorm Potential Metrics

List candidate metrics such as daily active users, photos uploaded, memories viewed, shares per user, or retention rate. Consider both engagement and retention aspects.

4. Evaluate and Select the North Star

Assess each metric against criteria: does it reflect user value? Is it actionable? Does it lead to long-term growth? Choose the one that best aligns with mission and goals.

5. Justify and Discuss Trade-offs

Explain why the chosen metric is optimal, acknowledge potential drawbacks, and mention how it can be supported by secondary metrics.

Key Points to Mention

  • The north star metric should capture the core value of Google Photos: helping users relive and share memories.
  • Consider 'weekly active users who view or share memories' as a strong candidate because it combines engagement and retention.
  • Avoid vanity metrics like total photos uploaded, as they don't necessarily indicate value.
  • The metric should be a leading indicator of long-term user retention and monetization potential.
  • Align the metric with Google's overall mission to organize the world's information and make it universally accessible.
  • Mention that the north star may evolve as the product matures, but it should always reflect user value.

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.