Here and there. Suppose your dungeon is full of ant people or orcs, creatures that can swing picks but are essentially dumber than the rocks they are hitting. They are rule followers and have not care for design, much like an algo. You can imagine an adventurer having to infiltrate such a place to steal a mcguffin, be it an uber-bee hive, an intestinal system of the dragon that ate you, or the random water paths that carved out a cave. The creator has to give the player a good reason why the system is random.