Why do we need a Leave Bank in addition to the VLTP?

Under the VLTP, employees in need of leave must rely on friends and co-workers to donate annual leave.  Should these requests for donations go unanswered, the Leave Bank is available. Under the Leave Bank, a reserve of leave hours is available to all Leave Bank members who are approved to be a leave recipient. Some employees choose the Leave Bank because it does not disclose medical emergencies.