And that's not a 90 day pre-fab building. IIRC, they had a dodgy underground carpark, which subsided. It had nothing to do with the actual building.
Also, the pre-fabs they are starting to build have a lot of steel, which is easy to engineer. Concrete can be more difficult to get right, especially when you don't trust the suppliers (bamboo rebar anyone?).
But concrete buildings are so common in China because they can be assembled with low-level migrant workers. The move to steel typically requires much higher-level expertise, and so only the tallest buildings get that treatment. But with prefab, this is interesting, they might be able to continue using low-level migrant workers in the factory and during assembly?
Also, the pre-fabs they are starting to build have a lot of steel, which is easy to engineer. Concrete can be more difficult to get right, especially when you don't trust the suppliers (bamboo rebar anyone?).