As email addresses go “bad,” your contact database or email list can atrophy. While this atrophy or list decay is inevitable, it’s not all bad.
Email addresses in your contact or marketing database can become bad for a number of reasons, such as changes to a contact’s job or name. Typically, marketing databases decay at a rate of 22.5% per year.
While you can’t do a lot about this kind of decay, you can ensure that you are regularly cleaning your list to improve deliverability and avoid high bounce rates which can diminish your sending reputation.
Losing email addresses can be discouraging, but losing invalid email addresses or reducing unengaged users lets you focus your efforts on quality contacts.