Activity items on tasks and notes give you a clear picture of why updates have been made—a full audit trail of what's happened. These activity items cannot be edited or removed.
When the start date or due date is changed on a task or note, an activity event will make a record of who made the change.
If an Automator updates the due date or assignee of a task, an activity event will make a record of it. It is clear that the change was due to an Automator, rather than a team member.
The event will include a timestamp, and information on which team member initiated the action.