lettmon: But did he really develop those games? Deus Ex on the other hand he was the main man behind, and after that only failures and flops, so you can call him a one hit wonder.
Harvey Smith was the Lead Designer on Deus Ex, Spector was credited (as usual) as Producer and Project Director despite Deus Ex being his brainchild. He filled the same role during the development of System Shock, so that either leaves him with at least two legendary games on his record or none at all.
Either way: no one hit wonder.