Money money money, paperwork and liability. I did the scaffolding for this apartment block being built by some local pair of millionaires. White geezers, like me. They hired these migrant brickies to do the first few floors. They were very cheap, but they weren't supposed to be there. Fast forward 4 floors and I'm in a lift shaft discovering a 60mm discrepancy, so unless they were installing a magical shrinking elevator, they just cost themselves about 50-100 grand in serious structural rectification brickwork purely to save what was probably much less than that hiring illegal workers for a few days/weeks. It's Earth, you don't get to be a millionaire unless you're abusing someone(s). Not a constriction centric issue. White people sell out their own every day, it's why we're losing/lost control over our own countries.