Confirmation of a chapter 11 plan providing for the reorganization or liquidation of a debtor is the culmination of the chapter 11 process. To promote the fundamental policy of finality in that process, the general rule is that a final confirmation order is inviolable. The absence of certainty that the transactions effectuated under a plan are valid and permanent would undermine chapter 11's fundamental purpose as a vehicle for rehabilitating ailing enterprises and providing debtors with a fresh start.