That's true about any engineering artifact though. If your steel rebar isn't built to whatever standard you require your concrete skyscraper isn't going to be s

That's true about any engineering artifact though. If your steel rebar isn't built to whatever standard you require your concrete skyscraper isn't going to be structurally sound. To build on top of the layers below you, you have to trust that they work, and when problems occur you fix the problems as they come up (or ideally prevent them ahead of time).