Complex sentence: In cases that arise in the normal course of editing, it is extremely important that the process should be carried through to its conclusion, and the rules updated, otherwise the rules will no longer reflect consensus, and again, then why have them ?
Split into simpler sentences: In cases that arise in the normal course of editing, it is extremely important that the process should be carried through to its conclusion. Otherwise the rules will no longer reflect consensus, and then, again, why have them?