Software is just as difficult to test because there are combinatorially increasing numbers of possible configurations and interactions in complex systems and so

Software is just as difficult to test because there are combinatorially increasing numbers of possible configurations and interactions in complex systems and software can potentially have an astronomically large number of interacting components. Additionally, software defects can and do kill people and cause billions of dollars in damage. A bug in the software for the Thorac-25 radiation therapy machine killed 5 people, for example. A bug in the engine control software of a Chinook helicopter led to a crash and the deaths of 29 British soldiers. During the Cold War software and systems errors almost caused the onset of a full-scale nuclear exchange between the US and USSR at least twice. It's difficult for consequences to get higher than that.