A best practice to keep deliverability high and bounce rate low is to routinely clear out all users that have bounced several times.
Iterable automatically unsubscribes users who hard bounce from whatever channel that email was sent from. These hard bounced email addresses can still cause future bounces however (if there's more than one marketing channel for example).
Users who soft bounce several times are probably not going to open future emails either, and this can negatively impact deliverability. Thus, we recommend going through a process of clearing these users out at least quarterly.
The overall process is to create a dynamic list that captures these users. Steps are below:
Create the dynamic list with a segmentation like the one below. You can choose however many bounces you'd like - the higher the number, the more conservative the clearing out will be. The list will be smaller if the number of bounces is higher.
In order to unsubscribe these users, click "Refresh" in the top right corner to search for users who meet the above criteria. Then click on "Export to CSV".
Go to Users > List and click "Channel Unsubscribe Users".
Upload the CSV file you just downloaded, select which channels you'd like to unsubscribe them from, and click "Remove Subscribers." We recommend unsubscribing users from all marketing channels, but keeping transactional channels open in case the user makes a purchase or does an action that prompts a transactional email.
Repeat this process periodically to help maintain an optimal deliverability and keep a low bounce rate.