New branch for deadline step
By specifying the event name for a missed deadline (of whatever type) you are indirectly telling the workflow system that you want to add flow logic to your workflow to meet this event.
Don't be put off by he fact that the branch does not lead anywhere. This is because the branch is not an alternative to the other results of the step. It is followed in addition to the other paths. In other words the workflow processing specified for a missed deadline is followed without affecting the standard flow. The step with the missed deadline remains where it is and can still be processed as normal