Exits remove people from a Workflow. Workflows retain an Exit at the very bottom and cannot be removed.
To add an Exit to a Workflow:
Click the + icon in the Workflow at the point you'd like people to exit.
From the pop-up, select Exit
When a person reaches an Exit, they'll be removed from the Workflow. The person can enter back into the Workflow if they satisfy the trigger event at a later time. However, it is not possible for a person to enter back into the position they held in the Workflow before they reached the exit point.