Let's ignore the fact that this may or may not be true (offshore code quality is bad) and just assume it's true... Why is offshore-developed code not the same

Let's ignore the fact that this may or may not be true (offshore code quality is bad) and just assume it's true... Why is offshore-developed code not the same quality? What is it about living (growing up?) in the US that has developers producing higher-quality code? I highly suspect that it's merely selection bias. US companies outsource offshore to save money and when your goal is to save money you've already decided that "the best" isn't really what you're going for. So the code we--as US-based developers--see from offshore development often looks like barely-working garbage. Yet if we look at open source code written by offshore developers it's often of high quality (i.e. higher quality than the crap we see in the world of Enterprise software). Why doesn't it match our experiences with commercial software development? It probably has a lot to do with incentives. Open source software is often developed for pleasure or as a learning experience whereas US companies outsourcing software development aren't exactly "driving excellence."