well, look as it this way: if that spacecraft would have went down due to an system failure... well... some astronauts would have died, they knew what they were doing... but if a plane crashes into the toronto tower, it could be /me :-D
@Technoid
if you argue like this, you should mention, that windows also is a pretty stable system, as long as you leave it alone, disconnected from net and all media removed ;-)