I've used map in the military - of Afghanistan - that were relinquish of old soviet maps. The soviet would have never got in many places of the desert and had mapped villages and roads from aerial photography. Those features would remain on our (US) maps.

As they rushed into the war, the geomatic guys responsible for making maps somehow reused the soviet maps and there was no way to assume those roads and villages didn't actually exist. So they persisted on our maps, up until 2010. Data around main areas would end up getting corrected (patrols would complain about the inaccuracy and the geo guys would update their database). Data in the desert would remain erroneous in many case.

For instance, I could simply look at a village's location on satellite imagery, such as a casual Google Map, and clearly see there was nothing there but maybe some odd looking shapes and shadows due to rock formations. So even hand-crafted maps, in military operation, almost 10 years into the war, can remain inaccurate.

Worst, maps of many military bases in North America are completely wrong as soon as you get off the few main roads listed on it.

I came to rely on satellite imagery whenever you want to go on a somehow non-urban track. It's much more reliable than using a map.