I worked for a while at a place that had a big immigrant employee contingent. It was palpable how much better the work ethic was among the non Americans, and how after a few years of being there they would get "Americanized" and start to become lazy like the rest of us.

I love America; this isn't a dig at American people. I think becoming lazy and not putting your heart into your working day is more a reaction to the level of exploitation of workers that exists in America, than some kind of personal failing on anybody's part. But that being said, the idea that immigrants are lazy could only come from someone who has not the slightest fuckin clue what they're talking about, academic analysis wise or personal experience wise or both.