Bounce rate
Percentage of sends that the receiving MTA refused. Hard bounces are permanent (invalid address); soft bounces are temporary (full mailbox, server down). Above ~3% sustained, ISPs throttle or quarantine your domain.
See also
Percentage of sends that the receiving MTA refused. Hard bounces are permanent (invalid address); soft bounces are temporary (full mailbox, server down). Above ~3% sustained, ISPs throttle or quarantine your domain.
See also