Discoveries and Dangers are two essential components to encounters. Every site (a place of interest) in a game session (within and outside of dungeons ) should have at least one potential encounter centering on a discovery or danger. They do no have to be pre-planned. They do not need to be obvious and in plain site. However, they should be something that can found and prepared for with a successful +10 Discern Realities roll. What the characters do with the information can trigger additional moves (player and GM). A discovery can unleash a danger if the characters mistreat it; a danger when defeated might reveal a discovery.
Anything the party finds that is interesting, but not an immediate threat. It might be: beneficial like a healing spring or friendly NPC worth exploring for the sake of potential adventure or accumulating lore. an obstacle like a broken bridge over a deep chasm that has to be dealt with or navigated around.
Anything which, if left unchecked, may be harmful such as a monster or trap. might be minor and incidental could part of or become part of a Danger in a larger Front.