What caused the sudden 50% decrease in successful transactions on Vinted's marketplace over the last 24 hours?

Introduction

The sudden 50% decrease in successful transactions on Vinted's marketplace over the last 24 hours is a critical issue that demands immediate attention. This analysis will systematically identify, validate, and address the root cause while considering both short-term fixes and long-term strategic implications.

I'll approach this problem by first clarifying key details, ruling out external factors, and then diving deep into the product ecosystem, user journey, and relevant metrics. From there, I'll generate data-driven hypotheses, conduct root cause analysis, and propose a structured plan for validation and resolution.

Step 1

Clarifying Questions (3 minutes)

• Looking at the timing, I'm thinking this could be a technical issue. Has there been any recent deployment or system change in the last 48 hours?

Why it matters: Recent changes often correlate with sudden performance drops. Expected answer: Yes, a new payment processing system was deployed. Impact on approach: If yes, I'd focus on technical hypotheses; if no, I'd broaden the scope.

• Considering user segments, I'm curious about the distribution. Is this decrease uniform across all user groups or concentrated in specific segments?

Why it matters: Helps determine if it's a global issue or specific to certain users. Expected answer: The decrease is more pronounced among mobile app users. Impact on approach: If segmented, I'd investigate platform-specific issues; if uniform, I'd look at core system problems.

• Regarding the metric itself, has there been any change in how "successful transactions" are defined or measured in the last week?

Why it matters: Ensures we're not dealing with a data anomaly or definition change. Expected answer: No changes in metric definition or measurement. Impact on approach: If changed, we'd need to audit the data pipeline; if not, we can focus on actual performance issues.

• Thinking about user behavior, have you noticed any significant changes in user engagement or listing activity preceding this drop?

Why it matters: Could indicate if the issue is on the buyer or seller side. Expected answer: Listing activity has remained stable, but we've seen a drop in buyer engagement. Impact on approach: This would help narrow down whether to focus on buyer-side or seller-side issues.