[c_o_n_v_e_x]

> IIUC, prefab construction is a labor arbitrage.

Industrial construction utilizes pre-fab all the time. Jackets, topsides, pipe racks and modules made in one country then shipped to the installation country (or territorial waters).

[jononor]

That sometimes is about quality. For example the quality assurance one can put into welding at a factory is much higher than what can be realistically guaranteed on site.