Control systems are a special case, where there is indeed no constant change. And there are more special cases like this, of course. But for most software, the

Control systems are a special case, where there is indeed no constant change. And there are more special cases like this, of course. But for most software, the customer keeps changing his mind and requesting new or different things. This includes hospitals. What's the impact of a bug have to do with it? I don't see the logic in "bugs are very bad -> this proves requirements don't change". Non sequitur. If you have not experienced this, you're very lucky. But look around, in this thread and elswhere, and see how many people are claiming the "adapt to constant change" claim of Agile is pointless. You'll find very few. Not that Agile is great. But this particular problem exists, and needs a solution. Software where requirements don't change is rare. It just is.