Zombies: How to resuscitate a database

When we think of a low quality database, with many inactive or non-existent users, outdated addresses, resulting in low open and click-through rates and poor performance of our email marketing actions, this scenario may come to mind:

But make no mistake, the landscape looks more like this:

Having a database that looks like this is pretty scary. The inactive users in our database may at first appear harmless, but in reality these records feed on our reputation and gradually diminish it. Out-of-date registrations that lead to high bounce rates are negative in the long term for the deliverability of our campaigns. Even without becoming bounces, inactive users who do not open our emails do a disservice to email marketing strategies.
So what do we do, eliminate them? Don't be so drastic... this is the last option. The first step is to try to save them. We must design a reactivation strategy, it will take some time but it will prevent us from losing users who can potentially add value to our list. Some ideas for this process:
1. Define what an inactive user is. How long has it been since you last opened/clicked on our emails?
2. Play with attractive topicsThe aim is to create a personalised, personalised campaign to arouse the interest of the inactive user.
3. Offer incentives.
4. Once a user has been reactivated works on the relationship to maintain interest and strengthen the relationship.
5. A reactivation campaign should include several successive emails in which we spend cartridges to attract the attention of the inactive user. Once we run out of resources, it is time to let them go. to ensure optimal performance of the mailing list.
Here is an example we discussed some time ago about a real case in which we applied a revitalisation strategy. You may also be interested in this article on the user lifecycle to establish a stable relationship and prevent users from "falling asleep".