Dungeon Master culture is knowing the next attack will almost definitely knock a PC, but making it anyway. While internally screaming and praying for a nat 1.
For me it depends. If it rolls initiative then it can die. Otherwise, I’m not gonna press the issue unless i am running low on plot and need a bad guy.
I love playing up the idea that I'm being an evil DM hell bent on a TPK which my players always manage to overcome. They're all good friends and know that's not what I'm really like but it almost becomes my own in game character. This meta BBEG they are constantly fighting