The go-to counterexample is the code that ran on the space shuttle, which took years and hundreds of people and $200 million to produce. I have been told that nobody has ever found a bug in the final production system. The development practices involved in creating it seem like they would make most software engineers want to curl up and die. One tidbit from the following link I found is that 60 people spent years working on the backup flight control system, intended to never be used!