There are several reasons why low delivery rates may occur:
1. Spam Filters: Modern email clients use sophisticated spam filters to weed out unwanted emails. If your email contains certain [keywords]() or patterns, it may be flagged as spam. 2. Invalid Email Addresses: Sending emails to [invalid addresses]() can result in bounces, which negatively affect your delivery rate. 3. Poor Sender Reputation: Your IP address or domain may have a poor reputation due to past email practices or spam complaints. 4. Content Issues: Emails with too many images, links, or certain phrases can trigger spam filters. 5. Lack of Engagement: If your recipients frequently delete your emails without reading them, email providers may start filtering your messages out.