OK. Maybe not the most PC thing or whatever but...It helps when the customer service agents are in the same part of the world as you and speak the same language.
Also, I use to work for a company in the travel business. When you have staff that take calls in this county you encourage "fam" trips at discounted rates for your employees. They get a trip at a really good price and learn first hand how the product works. This really help cust serv reps and customers speak the same language. Trip, add ons, insurance, etc. They get it. They live it. Things get lost in translation when the reps don't really live in the same world. There just is a lack of "ah, I get what your saying, looking for, concerned about, try to change, etc.