Why are Netflix My List items disappearing for 25% of accounts?

Introduction

Netflix's My List feature is a crucial component of the user experience, allowing subscribers to curate personalized content collections. The disappearance of My List items for 25% of accounts is a significant issue that requires immediate attention and a thorough root cause analysis. I'll approach this problem systematically, considering technical, user behavior, and product-related factors to identify the underlying cause and propose effective solutions.

Step 1

Clarifying Questions (3 minutes)

• Looking at the scope, I'm thinking this might be a recent issue. Has this problem emerged suddenly or gradually over time?

Why it matters: Timing can help identify potential triggers or changes that led to the issue. Expected answer: The problem appeared suddenly in the last week. Impact on approach: A sudden change would point towards recent system updates or data issues.

• Considering user segments, I'm wondering if this affects specific user groups. Are there any patterns in the affected accounts, such as device type, region, or subscription tier?

Why it matters: Identifying patterns can narrow down potential causes and guide our investigation. Expected answer: The issue seems to affect users across different segments randomly. Impact on approach: A random distribution would suggest a system-wide issue rather than a targeted problem.

• Thinking about system changes, have there been any recent updates to the My List feature or related backend systems?

Why it matters: Recent changes are often the culprit in sudden issues like this. Expected answer: A backend update was deployed last week to improve list syncing. Impact on approach: This would focus our investigation on the recent update and its potential side effects.

• Considering user feedback, have we received any specific complaints or error reports from affected users?

Why it matters: User feedback can provide valuable insights into the nature of the problem. Expected answer: Users report that their lists appear empty or show fewer items than before. Impact on approach: This would help us understand if it's a display issue or actual data loss.