>>3841265
Consider the traditional structure of an RPG (/tg/).
In the large majority of systems, and the more important ones historically - we find that the structure is vertical, with distinct levels that each have their own functional ruleset for play, as well as ways to move up or down to adjacent levels.
The lowest regular level of play is the combat. Above that is the level of the dungeoncrawl, and further above that is the hexcrawl (or another system that functionally provides the same purpose).
You traverse wide areas over large scales of time in the Hexcrawl to find a place of interest, once inside the place of interest you expolore and investigate what's inside through the dungeon crawl (acting in the range of minutes and hours), and upon coming into contact with a hostile the game moves to the level of the combat - with very specific rules and measured in seconds. Of course, the dungeoncrawl level can be skipped in some instances (a random encounter found while in the wilderness goes straight into combat from the hexcrawl), but the different levels are very distinct, and functionally serve to direct the purpose of the game -> you as a player want to kill monsters and get treasure (and exp), you find treasure and combat with monsters through dungeoncrawling, and you find places to dungeoncrawl through hexcrawling.
When taken to apply to video game rpgs, and the relevant Question here - the important thing is that separate dungeons necessitate interacting with the game on the "Hexcrawling" (here more often "World Map") level to transit between them, which separates the instances of the dungeoncrawling level of play.
