In the first picture they painted over failed concrete. The pictures are said to be “typical.”

The reasons it wasn’t evacuated at the time were business and politics not comprehensive structural investigation.

You see if the client isn’t paying to find problems below the surface, then they won’t be found. And it is common for clients to not want to find such problems. And for engineers to limit their analysis accordingly.

I know what my professional opinion would have been based on those pictures. It would not have been good for my business given the client profile.

Or to put it another way, those pictures show that what happened had a real chance of happening. That’s not hindsight. It would have caused me grave concerns.

As I have said elsewhere, the only thing I suspect is unique is that this was the first building to spectacularly fail.

It failed with people in it because there are tremendous disincentives toward saying the sky is falling even when the sky is falling. It's bad for business and it's bad politics.

Or to put it another way, suppose it was bad design or bad soil. Do you think that the same engineers, owners, contractors, and government agents did everything right on every other building? Think of how hard it is to keep salt off of rebar during construction next to the ocean. Now do so when there is every incentive to save money and no incentive to predict catastrophe.