What caused the sudden 30% increase in failed transactions on Simpl's Checkout platform last week?

Introduction

The sudden 30% increase in failed transactions on Simpl's Checkout platform last week 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 implications for our product ecosystem.

I'll approach this problem by first clarifying key details, ruling out external factors, and then diving deep into our product, metrics, and potential internal causes. We'll generate data-driven hypotheses, conduct root cause analysis, and develop a comprehensive plan to resolve the issue and prevent future occurrences.

Step 1

Clarifying Questions (3 minutes)

• Looking at the timing, I'm thinking this could be related to a recent deployment. Have there been any significant changes or updates to the Checkout platform in the past week?

Why it matters: Recent changes often correlate with performance issues. Expected answer: Yes, there was a minor update to the payment processing module. Impact on approach: If confirmed, we'd prioritize investigating that specific update.

• Given the scale of the issue, I'm wondering about its distribution. Is this 30% increase uniform across all user segments and transaction types?

Why it matters: Helps narrow down potential causes and affected areas. Expected answer: The increase is more pronounced in mobile transactions. Impact on approach: We'd focus our investigation on mobile-specific factors.

• Considering potential data anomalies, has there been any change in how we measure or define failed transactions recently?

Why it matters: Ensures we're dealing with a real issue, not a measurement error. Expected answer: No changes in measurement or definition. Impact on approach: Confirms we need to look at actual performance issues.

• Thinking about external dependencies, have we seen any changes in the performance or availability of our payment gateway partners?

Why it matters: External factors could be contributing to the issue. Expected answer: No reported issues from payment partners. Impact on approach: We'd shift focus to internal systems and processes.