Difficulty communicating with leads

• It will be more difficult to track your leads' responses. Every campaign report provides a range of information on open rate, click rate, unsubscribes, spam complaints, and bounces. When you delete and add lists, you won't be able to track your leads' responses across multiple emails. You may even lose track of which list was used in which campaign.
  
• A campaign report using one list can't be compared directly with the report from a campaign using a different list or the same list with a different set of leads.
  
• Lead engagement is useful for optimizing email deliverability and you can only track your subscribers reactions to help you refine future campaigns if you are using a consistent list.  
  

Lead engagement gap

• It is very easy to miss out some subscribers during the deletion and addition process, which may mean you lose potential customers. 
  
• If you do find some of those missing leads and send them emails after long engagement gap, they may not recognize your email and may mark you as spam.  
  

Duplicate campaigns

Loss of lists

When deleting and adding new subscribers manually, you risk:

• Typos
  
• Missing out some email addresses 
  
• Adding data in the wrong format
  

These errors will have a direct impact on your business returns.

The best way to avoid the issues listed above is to have a consistent list. You can closely follow your contact base and avoid deliverability issues caused by incorrect list maintenance.