Speaking specifically about the construction industry in California, because I am very familiar with that topic: Labor is less skilled, because of huge supply

Speaking specifically about the construction industry in California, because I am very familiar with that topic: Labor is less skilled, because of huge supply of undocumented workers. Also building codes and requirements for building safety have increased tremendously. Building a house in CA is WAY more complex than it used to be, since there have been so many requirements added to building codes over the years. Arguably CA houses are better built than they used to be, but the flip side is that it takes more time and experience to build one correctly.