The bounced email represents one of those metrics you can’t afford to neglect. In fact, it plays such a huge role in the overall quality of your list that regularly tracking it is considered essential to email marketing best practices
. Commit to monitoring your bounce rate after each and every campaign. If you do not, you will likely continue to send mail to invalid email addresses, wasting your efforts and potentially tarnishing your reputation as a sender.
An efficient reporting system will divide bounced emails into two categories: hard and soft bounces. While a hard bounce is classified as a permanent failure and a soft bounce is considered temporary according to Simple Mail Transfer Protocol (SMTP), the definitions of these two types of bounces are not always as cut and dry as they seem. For instance, a full inbox is one of the common causes of soft bounces. However, some internet service providers (ISPs) have been known to consider sending mail to a full inbox a permanent failure. With others, a temporary failure could become permanent if you do not reduce complaints or fail to address your bounces.
Though bounced emails are often confused in terms of their definition, distinguishing them is no less important. When analyzing your metrics, you must be able to determine whether it is safe to send a failed email again, and when it is time stop sending and start paring your house list. The worst thing you can do is nothing. Failing to address your bounces is the easiest way to fall into the spam traps purposely set up to block unwanted mail from their servers.