As this passage makes clear, the birthmark on Georgiana's cheek "expressed the ineludible gripe, in which mortality clutches the highest and purest of earthly mould." Aylmer's ambition, then, is nothing short of immortality for Georgiana and his distaste for the birthmark can be understood as antipathy for her very mortality, the quality that, ironically, makes her worth saving. To bring Georgiana to perfection is to bring her to stasis, or death.
Had she been less beautiful--if Envy's self could have found aught else to sneer at--he might have felt his affection heightened by the prettiness of this mimic hand, now vaguely portrayed, now lost, now stealing forth again, and glimmering to-and-fro with every pulse of emotion that throbbed within her heart. But, seeing her otherwise so perfect, he found this one defect grow more and more intolerable, with every moment of their united lives. It was the fatal flaw of humanity, which Nature, in one shape or another, stamps ineffaceably on all her productions, either to imply that they are temporary and finite, or that their perfection must be wrought by toil and pain. The Crimson Hand expressed the ineludible gripe, in which mortality clutches the highest and purest of earthly mould, degrading them into kindred with the lowest, and even with the very brutes, like whom their visible frames return to dust. In this manner, selecting it as the symbol of his wife's liability to sin, sorrow, decay, and death, Aylmer's sombre imagination was not long in rendering the birth-mark a frightful object, causing him more trouble and horror than ever Georgiana's beauty, whether of soul or sense, had given him delight.