If our Will comes from the Good, why is it not refined, and sent up?

For if our Will lessens Evil, that statement is conquered whereby they say that Evil is mixed with Good, and behold (they say) "the Good is refined little by little." For behold our Will is in us always, and is not 'refined at all, nor does it go out from us.' For if our Will 'were being refined and going out,' our Will would have already come to an end, and it would not be possible for us to will rightly. And if our Will does not come to an end neither do Good and Evil. When, [xxvii] therefore, does the Refining and Separation of the two take place ? [Ov. p. 57.] And if there is a Refining of the Good by means of Good so that it goes up from the Depths to the Height, why is there not also a removal of Evil by means of Evil so that it may be sent down to its Depths ?