Expats do almost all the work. Depending on where they are placed, some see lots of action, some don't.
Expats gotta take care of themselves. Since the company provides no training opportunities, and no career prospect.
When things go well, expats don't get the glory. Because expats tend to stay in the background; the locals are the face of the organization, internally and externally.
When things go bad, expats get all the blame.
All the company can offer the expats is money and, for those who get to live inside the camp, a good family environment. But when the money runs out.....