I notice that quests are spawned on the map and sometimes when I walk over them a quest is not triggered.

I just discovered that these are redoable quests and since I was already actively doing this quest, the other quest spot was not triggered. Once I finished the other quest I can now activate or trigger this quest.

I wouldn't mind it if a person finishes these redoable quests that another always spawns after it is complete (future feature wish). But something needs to tell the player something about this questing location, for example

"Currently there looks to be nobody here, you should come back later after you finished some quests."

Although, this might be another feature request. Something needs to happen here so people are not confused why certain quest locations are not activating.