Someone I know who has moved across multiple cultures in professional and personal situations said, "Each country has a different User Manual." This includes practical stuff like how to get things done, and also includes such things as cultural context for, say, a smile. His theory is that it takes time to get to know the User Manual and it's difficult to do remotely.

The thing is, when you're writing to an audience deeply grounded in, say, US culture, you can show the situations of a different culture but you can't easily share the values.