Running a relay for an app that sends public notes (such as Damus) is much more challenging than for an app that sends private notes (such as Keychat). When a Keychat message recipient receives a message, the relay can delete the encrypted message, or at most store it for one month, resulting in minimal storage pressure. However, a public note is intended to be stored for a long time so that future readers can access and read it, which significantly increases the storage burden on the relay.