Fix the content first. On a page that is not ranking, content quality is what decides whether it deserves to rank at all, and Core Web Vitals only come into play once it does. The instinct to clear the technical work first inverts the order, because vitals only break ties among pages that are already competitive, and a page no one is competing with has nothing for that tiebreaker to decide. Fix the reason the page is weak before reaching for the polish.
The logic follows from what vitals actually do. They separate pages that already match on relevance and authority; the faster of two strong contenders edges ahead. But that mechanism never activates for a page that has not earned its way into contention. If the page does not answer the query, lacks the depth or the supporting authority to rank, then perfect vitals change nothing, because speed is not the thing holding it back. Polishing the load time of a page that does not deserve to rank works on the wrong layer entirely.
There is one condition that flips the priority. If the vitals are broken badly enough to block the page outright, slow to the point that rendering fails or the experience collapses, then that breakage is its own barrier and has to be cleared before anything else can matter. Merely scoring in the Needs Improvement band is a different matter; a genuine block comes first, ordinary imperfection waits.
So the editor fixes the content’s relevance and depth before chasing vitals on a page that does not rank, treating the technical metrics as the final edge to add once the page is good enough to compete, not the first thing to repair.