The resolution of commercial disputes by arbitration is generally seen as more efficient than court proceedings. To a large extent, such perception is due to arbitral awards being enforceable shortly after being issued by the arbitral tribunal, because they are normally not subject to appeal and their annulment by the courts is only admissible in exceptional circumstances. Those in favor of one-instance arbitration argue that reviewing an arbitral award by someone other than the arbitral tribunal would undermine the main benefit of arbitration (i.e., the speed at which a final decision can be reached).
Moreover, unlike state judges, who are designated according to impersonal criteria, arbitrators are appointed by the parties amongst people they trust. Save in special circumstances, each party appoints one member of the arbitral tribunal, and the third arbitrator is selected by the co-arbitrators so appointed. Hence, because the arbitral tribunal is formed according to the will of the parties, its decisions should presumably be final and binding on them.
On the other hand, the right to appeal a decision taken by an adjudicator—the so-called double degree of jurisdiction—is a most valued principle in civilized countries. The losing party's right to have its arguments reviewed by a higher body of adjudicators has, for a long time, been a warrant against possible errors of fact or law by the arbitral tribunal. Thus, appellate review is a means to reach the best possible decision for the case and a way of giving the losing party the certainty that the decision has been duly analyzed, and either upheld or reversed by a reviewing body.