Engagement is a subscriber-based estimation of how engaged subscribers are with your email, i.e., the chances of subscribers opening your email, how much time they spend on it, clicking and replying to them, foldering, and performing similar positive explicit actions. Engagement is considered a crucial success metric. It is a strong indication of how legitimate your mails are to your subscribers, which will ultimately inform their decision of placing it in their inbox or not.
Your email engagement is the assessment of how recipients interact with your email – do they open your emails, do they read, do they click on the links, or follow the call to action?
Email marketers use engagement as a metric to improve the future design and make better content decisions to ultimately make their campaigns more effective.