[guiriduro]

If I remember, the earlier systems had a hardware lock that prevented an overdosing for whatever reason, including software fault. Sure, the software was still faulty, but don't forget if software was developed for a particular hardware such that a certain concern could be discounted (even if it ought to have been tested for) - is it really the developer's fault when the manufacturer (presumably for economic reasons) decides to remove safety features and increase the risk surface?

[brazzy]

According to Wikipedia, the new model was actually deemed safer in an audit on the grounds that unlike a mechanical lock, the software could wear out or get damaged. So it seems more likely that people generally had a very mistaken view of software reliability.

[jrootabega]

I assume you mean software could NOT wear out or get damaged

[brazzy]

correct