[russnes]

I'd say one of the best features for private messaging is having disappearing messages. Then you lower your chances of leaking the messages to someone gaining illegitimate access right now, instead of leaking the database at any time in the future

[papito]

Are you positive that the massages disappear from your device AND from the servers?

These companies notoriously do not delete anything ever. I am sure that even the things they are required to delete by law are removed, compressed and stashed somewhere.