This speaks to the good work of engineers (and architects). So few buildings ever fall down. That means nearly all were "built right."

I recall the story of the collapse of the department store in South Korea. The building was handed to the owners, and the owners decided to put a big kitchen on the top floor. The building was not designed for this extra weight at the top. It still held, but after years of too much weight, things gave way.

The city of Calgary is going through a similar process. In the 1970s they built a big water line. It was expected to last for 75 years. This summer, it broke down, putting the city in a near water shortage.

Investigations are happening. It kind of sounds the pipe should have been covered in sand and gravel, not soil. Too much corrosion. In this case, the engineers of the 1970s perhaps did the best with the knowledge they had. But it's kind of hard to fire them today.