We work with an internal and an external team throughout an item's lifecycle. Both sets of users are assigned to an item throughout. But we don't want to send notifications of our internal workings to our external team through the process.
As updating statuses within items is the only way we can leave messages for our internal members, we want to be able to de-select assigned users (padlock) from the 'notify and complete' function. They can be populated automatically there as assignees, but we want to be able to remove them if needed.