Cart abandonment occurs when shoppers add items to cart but don't complete checkout. The average rate is about 70%, representing massive opportunity. Common reasons for abandonment: - Unexpected costs (shipping, taxes) - Required account creation - Complex checkout process - Security concerns - Just browsing/comparing - Found better price elsewhere Recovery strategies: - Abandonment emails (within hours) - SMS reminders - Retargeting ads - Exit-intent popups - Simplified checkout - Guest checkout option - Price guarantees