This mode of government must be understood as one in which all the rest of the Partzuf is complete except for the supports that give it the ability to stand. For Chessed-Gevurah-Tiferet are the body of the Partzuf while Netzach and Hod give it support and Yesod and Malchut channel the influence to the lower worlds. Of the two supports, one is complete but the other is not. This is so that the world, while having a place for flaws, will not be destroyed. (For this reason Hod is still not completely repaired and as a result Netzach is also subject to flaws, because when one leg is flawed the second leg also cannot function properly.)
This is also bound up with the various exiles – the main period of exile was in the fifth millennium corresponding to Hod. The flaw in Hod affects Yesod and Malchut, through which the influence is channeled. Netzach and Hod are the secret of the two Messiahs, as stated in the Zohar (Pinchas 252a). This requires a separate process of purification in addition to the first.