Exit calls directly relate to exit rules, which are queue policies designed to prevent overflow and unproductive practices.
The rules are triggered when certain thresholds are met in a queue. When that happens the triggering call is moved to a predefined destination. Triggers can be excessive hold time, agents that are not logged in, or a specific limit for the amount of calls. Destinations can be a voicemail, another agent, other queues, a specific extension etc.
For example, if a client was holding for more than ten minutes an exit rule will be triggered and move the call to another queue. Or if an exit rule is set to maximum of twenty-five calls than the twenty-sixth call overflowing the queue will move that call to a specific agent.
Exit rules are set in the general settings of the Queue Manager. See the Queue Manager user guide for more info.