Well quite simply, it means exactly that. Namibia has a wide road network and it is not permitted to drive off road and create new tracks. Being mostly a desert, tracks left behind can stay there for many years, in some cases, decades. Driving off road also means possible vehicle damage, especially under carriage which is not covered in any insurance claim. In other words, stick to the designated roads and don’t wonder off into the wilderness. Dune driving is definitely not allowed either. Trust us, Namibia is enough of a “off the beaten track” destination as it is, so you won’t need to venture off in any case.