...almost always made of softwood two-by-fours, or “stick,” in construction parlance, that have been nailed together in frames like those in suburban tract houses.
The method traces to 1830s Chicago, a boomtown with vast forests nearby. Nailing together thin, precut wooden boards into a “balloon frame” allowed for the rapid construction of “a simple cage which the builder can surface within and without with any desired material,” the architect Walker Field wrote in 1943. “It exemplifies those twin conditions that underlie all that is American in our building arts: the chronic shortage of skilled labor, and the almost universal use of wood.” The balloon frame and its variants still dominate single-family homebuilding in the U.S. and Canada.
“You can make mistakes and you can cut another piece...” “With concrete and steel, it’s just a lot more work to fix problems.” ... If supplies run out ... builders “know they can run to the nearest big box and get what they need.”
Stick construction allows builders to use cheaper casual labor rather than often-unionized skilled tradespeople. And it makes life easier for electricians, plumbers, and the like because it leaves open spaces through which wires, pipes, and ducts can run.
https://www.bloomberg.com/news/features/2019-02-13/why-america-s-new-apartment-buildings-all-look-the-same