the only explanation

from here

so, amazingly, people in high places (get it?) seem to think that the computers that got infected with the shamoon virus HAD to be replaced as a result of either infection or it's data damaging payload. that's right, not just disinfected, or re-imaged, or formatted and re-installed, the computers in their entirety had to be replaced. apparently these people have never heard of malware recovery or disaster recovery - or maybe they were just high as kites.

(one wonders, by the way, why vendors would be so shy about calling a piece of malware that self-replicates across the internal network a virus or at least a worm)