Game concept
Privation
From the game's encyclopedia
When a Camp is stationary, they can sustain themselves with bartering food for odd jobs, hunting, foraging, or fishing where allowed and possible, and generally just about treading water on their supply situation.
As soon as they have to start Traveling, they're entirely reliant on their Provisions to survive, since they cannot both move and obtain sufficient food. As Provisions run low (then run out), tempers will flare and Followers will starve.
When this happens, Characters will begin to leave the Camp, negative Modifiers are increasingly applied, and those who remain will eventually mutiny or die.
The game's text for patch 1.20.1.2. Words in blue are entries of the encyclopedia: hover one to read it, as in the game.
Privation is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "When a Camp is stationary, they can sustain themselves with bartering food for odd jobs, hunting, foraging, or fishing where allowed and possible, and generally just about treading water on their supply situation." It is part of Provisions. Patch 1.20.1.2, from game/common/game_concepts/00_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/00_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.