Email deliverability and the impact of engagement metrics

Email deliverability is a critical factor for marketing success, determining whether messages reach a recipient's inbox or are diverted to spam folders. Key challenges include technical infrastructure settings, authentication protocols, and sender reputation. Using untrusted IP addresses or failing to meet compliance standards can trigger spam filters.

Effective deliverability relies on maintaining high subscriber engagement and performing regular list hygiene. Marketers are encouraged to focus on engaged segments—subscribers who have recently opened, clicked, or signed up—to improve inbox placement.

Furthermore, the accuracy of engagement metrics is being questioned due to 'open bloat.' Privacy features, such as Apple Mail Privacy Protection, can automatically load email content, creating artificial open rates that do not reflect actual human interaction. This has led some industry professionals to view traditional open rates as a 'vanity metric.'