Email Marketing's email analytics track multiple types of bounces for you and handle them slightly differently. If you need more information, we have a guide to bounces where you can read more about specific bounce types.
It’s tempting to keep older subscribers even when it’s clear they’re no longer reading campaigns, but unresponsive contacts can lower your email marketing impact. It’s better to remove the older, unresponsive contacts and keep your list of senders fresh.
Think of your email list as a fluid resource. When you clear out the old, you make room for the new. New sign-ups are often the most engaged portion of your list. Pruning your list regularly leads to increased view rates and greater list growth in the long term. It tells ISPs (internet service providers) you're serious about keeping your list healthy and this keeps your delivery rates high.