liveanddieby (third-person singular simple presentlives and dies by, present participleliving and dying by, simple past and past participlelived and died by)
(idiomatic) Be completely reliant upon.
2019 November 21, Samanth Subramanian, “How our home delivery habit reshaped the world”, in The Guardian:
The e-commerce industry lives and dies by metrics, a few of which give us some grasp over this phenomenon.