A “bounce” means the email didn’t arrive, for any of a number of reasons. But, that doesn’t necessarily mean the email address is bad.
Good addresses can bounce if the mailbox is full, the server is having temporary issues, or if it gets blocked or put in junk folders. This is called a soft bounce and is considered a temporary error, most commonly “Mailbox Full.” So, this does not necessarily mean the email address is bad; RatePoint will keep trying and will not automatically remove this address from your contacts list.
A hard bounce typically means the email address itself is bad.
In general a SOFT BOUNCE = Temporary error, and a HARD BOUNCE = permanent error.