Perhaps several mobs share the same combat pattern, but with different parameters. Grievously wounded Greydwarves will now flee from the character (to return (much) later).
Boars and Nekkes will sometimes first flee from the character (when not triggered).

Originally posted by us271934:

Since the Black Forest has quite a few pathing obstacles it may be they were just trying to get closer to me.

This is why, when I'm landing on a shore in Black Forest, I don't remove old trunks and stumps, nor any trees, up to 50 meters from my campfire. More spots to hide, more obstacles to delay the enemy.