Vegan smoothy jokes aside, this is a serious matter, and it’s closely connected to engagement. These two indicators directly affect each other — and email health, too.
The delivery rate is the percentage of emails that reach the recipients’ inboxes. Each email that gets bounced, marked as spam, or caught by the ESPs’ filters, lowers this percentage. That, in turn, lowers your sender reputation, and that affects both delivery and engagement rates… You know the drill.