We were told an example of this at the university, but unfortunately I can't remember the company in question. Anyway, the story goes that an American or European pharmaceutical company wanted to enter an Arabic market with pain-killers. They made a "cartoon strip" ad, probably for the same reason zav200 mentions; illiteracy. This cartoon showed three images from left to right:
1) a woman with a headache
2) the woman taking a pill
3) the woman being happy

What they failed to realize, is that in Arabic you read from right to left...