Terminating a subscriber can be a sensitive decision. Here are instances when it might be necessary:
Inactivity: If a subscriber hasn't opened or engaged with any emails over a significant period. Unsubscription Requests: Prompt action is required when a subscriber requests to be removed from the list. Hard Bounces: When emails bounce back due to invalid addresses, removing these addresses helps maintain list quality. Spam Complaints: High spam complaints can damage your sender reputation; hence, removing such subscribers is crucial.