Ships are far more isolated than land crews, and direction-finding is much harder at sea than on land. If you're part of an organization that cares where you are and wants you back, you are pretty easy to find your general location venture off on a land journey and get stuck. A single human might be hard to find under a rock or snow, but an army unit that wants to fund is easy to spot.
The problem with getting lost as an army unit on land is that you might inadvertently get in your enemy's sights before anyone on your side might have had the chance to find you, and at that moment it is game over for said unit. There have been documented a few of these such cases in the war in Ukraine.
