For Spotify personalization drives a huge chunk of listening through algorithmic playlists (Discover Weekly, Daily Mix), optimizing for listening time to achieve as much freemium conversion as possible. Premium represents around 90% of revenue for Spotify, with good personalization and playlists curated for you and stuff like spotify wrapped creating emotional lock-in, they reduce churn and keep building monthly revenue..
LinkedIn uses a feed algorithm optimized for professional relevance and session frequency using near-real-time features. They want a small increase in weekly active users (huge at scale) maximizes ad inventory value, with personalized professional content driving habitual check-ins for premium B2B ads.
The TikTok For You Page analyzes engagement, completion rates, and behavior to optimize ad targeting precision. The better optimized the videos are to your likes, more time you spend, the better profile they have of you, and the more ads they sell. Users spend hours daily, creating “inventory” in the sense of peoples attention, and behavioral prediction transforms attention into advertiser conversions, which is the most profitable thing for them. Personalization ROI varies by revenue model—Spotify converts engagement to subscriptions, LinkedIn converts relevance to session frequency (ad inventory), and TikTok converts behavioral prediction to advertiser spend.
