Automatic removal can be initiated through several mechanisms:
Hard Bounces: These occur when an email is returned to the sender because the recipient's address is invalid. A high number of hard bounces can harm your sender reputation. Spam Complaints: If a recipient marks your email as spam, they are often automatically removed from your list to prevent future issues. Inactivity: Many email marketers set up rules to remove subscribers who have not engaged with emails over a certain period (e.g., six months).