Well, this is not uncommon to me. I live in a country where some of the rurals areas roads such as those exist. The reason, mainly, because roads are expensive. Not every country in the world can afford to have all land based surface for traffic to be paved, either by asphalt concrete or portland cement concrete.
You people will be suprised how people transit those roads anyway, despite their conditions. Well, just to ease those who might be concerned the most important highways and secondary here are already paved, so only some internal roads and roads connecting towns will be found in such conditions.