Why do Slack direct messages disappear?
By default, Slack will keep all messages for the life of your workspace. Workspace owners and organization owners can change retention settings for individual public channels. If allowed, members can also set a custom message retention period for the private channels and direct messages (DMs) they are a part of.Slack does not archive deleted messages or provide a way to recover deleted information. Once a user deletes a particular message, that message disappears forever. However, Slack can still retain deleted message information that can be included in an electronic tracking export.