Some businesses have a requirement to manage customer preferences in their own system externally to SFMC. In this scenario, there is a risk that publication lists in SFMC may not be updated in real-time. For example, if a contact opts out of a publication, and your publication list is updated via an automation that fails, some contacts may still receive the publication. Here is a safeguard approach to protecting against contacting the wrong people in a journey:
Add Exit Criteria to the journey, which is evaluated when a contact’s time in a wait step ends.
EMAIL_OPT_IN equal false OR MY_NEWS equal false
Add a Wait activity before the Email activity. This can be as short as 1 minute.
In this real example, 30 people were excluded from receiving the send because they had opted out from the publication, via an external webpage to SFMC. Preferences were synced back to a non-sendable DE via API.