I don’t think that’s accurate. Purging means passively suffering for your own sake. If you want to suffer for others you better do it here and now. I think that’s the freightening thing about purgatory, that there’s nothing you can do about it except wait it out. Purgatory is a place where we heal of the effects of our sins and imperfections.
I remember hearing or reading an authoritative source (perhaps at audiosancto) that purgatory is both joy and suffering at the same time. Joy because we no longer sin and are anticipating the beatific vision in peace, but suffering because of the current deprivation of the beatific vision.