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McKinsey·Software Engineer·Onsite - Product Sense / Strategy·Intermediate

Intermediate
Jun 2026

Summary

McKinsey data science interview with a classic consulting case framing. One question, profit decline scenario, felt more like a business analyst screen than anything technical.

Questions Asked (1)

Q1

A client's profits have dropped by 20%. How do you approach diagnosing and addressing this?

Root Cause AnalysisProduct Analytics & MetricsProduct Strategy
Author's notes

I went straight to revenue vs cost decomposition which felt right, but I spent too long on the revenue side and kind of glossed over margin compression.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the scope and timeframe of the profit drop, then systematically break down the problem into revenue and cost components using a data-driven approach. Prioritize hypotheses based on the most likely drivers, validate them with available data, and propose targeted solutions with measurable impact.

Pro tip: Emphasize that you would first check whether the 20% drop is a one-time anomaly or a sustained trend, and compare it against industry benchmarks to contextualize the severity. This shows strategic thinking and avoids overreacting to noise.

1. Clarify and Scope

Ask clarifying questions to understand the profit metric definition, time period, business unit, and whether the drop is sudden or gradual. Confirm the goal: is it to diagnose, fix, or both?

2. Break Down the Problem

Decompose profit into revenue and costs. Further split revenue by product, customer segment, and geography; costs into fixed and variable. Identify which components changed most significantly.

3. Analyze and Hypothesize

Use data to identify correlations and outliers. Form hypotheses about root causes (e.g., pricing changes, increased competition, operational inefficiencies) and prioritize based on impact and ease of validation.

4. Validate Root Causes

Test hypotheses with targeted analyses, such as cohort analysis, funnel metrics, or cost audits. Engage stakeholders to gather qualitative insights and confirm findings.

5. Recommend and Implement Solutions

Propose actionable solutions with expected impact, effort, and timeline. Suggest a pilot or A/B test to validate before full rollout, and define success metrics.

Key Points to Mention

  • MECE (Mutually Exclusive, Collectively Exhaustive) breakdown of profit into revenue and cost drivers
  • Use of data analytics tools (SQL, Python, dashboards) to query and visualize trends
  • Prioritization frameworks like impact/effort matrix or 80/20 rule to focus on high-impact areas
  • Consideration of external factors (market trends, competitor actions, regulatory changes)
  • Collaboration with cross-functional teams (finance, product, marketing) to gather insights
  • Proposal of measurable solutions with clear KPIs and iterative testing

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