I always write chapter titles because I'm one of those weird readers who appreciates a good title (for fantasy anyway).
Sometimes I write the chapter first and then name it so the title fits the tone of the chapter.
Other times I name it because I actually know what's supposed to happen.
My chapter titles also have (please read this like some immortal being) SYMBOLIC POWER *lightning sparks as the earth trembles beneath you*. In the first novel, there's only one POV, which is my MC and all the chapter titles start with "the" (e.g. The Raid). BUT in the second novel, the POV is split between my MC thread and her twin sister's thread. For now, they're going to have the same chapter titles, but the one's for my MC will start with "the" and the ones for her sister will start with "a". Yes, it's complicated, but it makes me happy.
I also have this "log" thing where my MC does a reveal of emotions/inner thoughts, just so I can create a closer POV. The journal that she uses is also very important in the storyline and I didn't want it to be forgotten.