Even the best paying newsletters deal with churn. Churned subscribers are ones who have downgraded from a paid plan to a free plan but remain subscribed to your newsletter. This may happen for a number of reasons:

• Their payment method failed and they never updated it.
• They decided your newsletter wasn't worth paying for. (How rude of them!)
• They found your newsletter valuable, but something was keeping them from staying a paid subscriber.

Whatever the reason, you can now send emails directly to churned subscribers. This is a great way to try to win them back or learn more about why they churned. (Maybe send them a survey!)