Full Answer

Server-side tracking improves ROAS through two mechanisms: (1) Capturing conversions that client-side misses (30-40% data loss recovered), so platforms see your true performance; (2) Sending enriched data (hashed emails, customer IDs) that improves match rates and closes cross-device attribution gaps. When Facebook/Google algorithms train on complete data instead of 60-70% of events, they find better audiences and optimize more effectively.