The tragic irony is that, if Bonin had taken his hands off the flight stick, the plane would have stayed in the air. So the most immediate, obvious conclusion is to simply blame Bonin for the crash. His actions did crash the plane. His co-pilots overlooked his mistakes. But that conclusion is missing a pretty obvious point: Bonin and his colleagues were all trained, experienced pilots who would have made different decisions with better feedback. We can blame humans for every error in the world, at some level, but the point of good design is to understand human nature, accommodate it, and most importantly, enable it.