Yamato and the cost of concentrating an industrial effort

How did Japan acquire the industrial capacity to build its largest battleships?

By concentrating resources on Yamato and Musashi and accepting that other claimed construction activity did not represent equivalent real output.

The answer emphasizes that Yamato and Musashi absorbed a concentrated national effort. Japan directed so much of the relevant industrial capacity into the two battleships that little comparable construction could proceed alongside them. Claims that cruisers and other ships were also being built helped conceal the concentration but did not create additional output. The example separates secrecy about a programme from the much harder problem of supplying the factories, labour, and materials needed to execute it.