Currently when a contact is added to a list, the "added to" list membership event is visible as an activity on the contact record. But when the contact leaves the list, the "added to" event is removed from the contact record. Because of this, we are not able to see if a contact has ever been member of a list in the account UI.
This makes it hard to understand why a contact was enrolled in a workflow that is based on list membership, as there is no visible record that the contact was part of the list at some point in time.
We need a function to be able to see when a contact is added and when a contact leaves a list, on the contact activity timeline.