An eligibility-limitation concept defining grounds that bar admission or benefits and mechanisms to overcome certain bars through waiver adjudication. It specifies disqualifying conditions and the required showings for discretionary or statutory waiver approval where available. It does not remove disqualifications that are nonwaivable and does not excuse failures to meet separate benefit eligibility requirements. It determines whether an applicant can proceed to admission or benefit grant and often drives evidentiary and timing burdens. The concept is generally stable, though waiver criteria and disqualifying grounds may be revised over time.