Death is an mysterious thing. Death means end of a persons life and the beginning of eternal slumber, unless resurrected or risen from the death as a mindless creature, hungering only for the living.
Sometimes, when a creature of the undead is finally freed from the necromancers spells, the person regains his/hers mind and will to live, yet staying as an walking corpse.
For some, it's an curse, for others it's an new start. For few rare, it gives them the eternal beauty they were trying to get when living.