The Night King doesn’t have a choice; he was created that way, and that’s what he is.
In some ways, he’s just death, coming for everyone in the story, coming for all of us.
WEISS: I don’t think of the Night King as a villain as much as, Death.
The Night King certainly unleashed his wrath on Bran’s weirwood base this season, though one wonders what he and the other White Walkers otherwise spend their time on, to have avoided breaching The Wall for so long.