Because it's unacceptable that the aid worker's chauffeur only speaks his own tribal language, an applicant is needed who also speaks English fluently - and, ideally, one who is also well mannered. So you end up with some African biochemist driving an aid worker around, distributing European food, and forcing local farmers out of their jobs. That's just crazy!
If I have learned one thing in my 54 years, it is that it is very good for the character to engage in sports which put your life in danger from time to time. It breeds a saneness in dealing with day to day trivialities which probably cannot be got in any other way, and a habit of quick decisions.