She told Yinan that fire must burn, and burning reflects its value and meaning. Even if there is only one ending, it still has to make itself bright. Only in this way can it be considered alive.
But retroactively, living burning must destroy other things in order to make itself bright. This kind of burning is endless. When it is extinguished, it cannot restore those destroyed things. It will only bring an end. Yinan said this.