Machine Learning System Design Interview #8 - The CTR Feedback Loop Trap
When “High Engagement” Is a Lie: The Hidden Failure Mode of Recommender Systems
Your 𝘊𝘭𝘪𝘤𝘬-𝘛𝘩𝘳𝘰𝘶𝘨𝘩 𝘙𝘢𝘵𝘦𝘴 is hitting all-time highs. Your retraining pipeline is executing perfectly every 24 hours. But user retention is quietly tanking.
The VP of Engineering asks the candidate why your “successful” model is killing the product.
If they answer “Maybe the content quality dropped,” they just failed the interview.
