What factors are causing the sudden spike in failed transactions for Nequi's QR code payments system this week?

Introduction

The sudden spike in failed transactions for Nequi's QR code payments system this week presents a critical issue that demands immediate attention and a thorough root cause analysis. As we delve into this problem, we'll employ a systematic approach to identify, validate, and address the underlying factors contributing to this performance decline. Our goal is not only to resolve the current issue but also to implement measures that prevent similar occurrences in the future.

Step 1

Clarifying Questions (3 minutes)

• Looking at the timing, I'm thinking there might be a recent system change. Has there been any software update or infrastructure modification in the past week?

Why it matters: Recent changes often correlate with sudden performance issues. Expected answer: Yes, a minor update was pushed last Tuesday. Impact on approach: If confirmed, we'd prioritize investigating the update's impact.

• Considering user segments, I'm curious about the distribution of failures. Are we seeing a uniform increase across all user types, or is it concentrated in specific segments?

Why it matters: Helps narrow down potential causes related to user behavior or specific features. Expected answer: The spike is more pronounced among high-volume merchants. Impact on approach: We'd focus on merchant-specific factors and high-load scenarios.

• Regarding the definition of "failed transactions," has there been any recent change in how we categorize or measure these failures?

Why it matters: Ensures we're not dealing with a measurement anomaly rather than an actual increase in failures. Expected answer: No changes in failure categorization or measurement. Impact on approach: Confirms we're dealing with a real increase in failures, not a reporting issue.

• Thinking about external factors, have there been any significant events or promotions that could have led to an unusual surge in transaction volume?

Why it matters: Unexpected volume spikes can strain systems and lead to failures. Expected answer: A major retailer started a promotion using Nequi QR payments. Impact on approach: We'd investigate capacity issues and potential bottlenecks in high-volume scenarios.