There are two ways AWeber informs users about complaining subscribers:
By reviewing the two, your complaint rate can be determined, so that you can review the performance of your messages, be aware of potential issues, and better understand your subscribers.
This in turn can help you to optimize your email campaigns.
Reviewing Complaints in the Control Panel
To review complaints for broadcast messages in a campaign:
Hover over the "Messages" tab and click "Broadcasts".
Under the "Sent Broadcasts" section, you can see the number of "Complaints" issued for the message.
Reviewing Complaints By Email
When complaints are made about your follow up messages, AWeber will periodically send you an email message.
Along with a brief explanation of feedback loops, the message gives information on the list containing the messages that are causing the problem along with suggestions on steps that can be taken to reduce complaints in the future.
Since, as opposed to broadcast messages, which are sent once at a specific point of time, follow ups are sent continually over a period of time, these emails will keep you up to date on complaint trends for your messages.