More on Zombie Lord

Forgot to mention this, sorry about the double-post. The helpfile states... ZOMBIE LORD Zombie Lords are necromancers who discover they have a knack when it comes to the animation of the dead. These black magicians can raise the dead with greater ease, and are much less likely to destroy their corpses of choice. I am confused about the last part there...every time I fail to raise something the corpse still, as always, is destroyed. Is there supposed to be a chance that the corpse remains or something? P.S. Just failed zombie raising number 4.