What is bounce rate?
This is the percentage of email addresses in your mailing list. Your email was not delivered because the recipient mail servers returned this message. These are “reflections” that occur when an e-mail message cannot be delivered to e-mail addresses.
Bounce rate can be divided into two types. One is the so-called Hard bounce rate, where the reason for not breaking the e-mail message is the absence of an e-mail address. The second type is Soft bounce rate. For Soft bounce rate, the non-delivery of an e-mail consists in rejecting the delivered e-mail, for example due to the overcapacity of the e-mail box.