Google has confirmed there are hundreds of ranking signals and thousands of variations. You don't need to know all of them, you need to know the categories and which ones matter for your query types.
How well does this page match what the user searched for? Signals: keyword usage, synonyms/entities, content depth, query-to-content semantic match.
How trustworthy is the source? Signals: backlinks from authoritative sites, domain age, topical consistency, brand mentions, E-E-A-T signals.
Will users have a good time on this page? Signals: Core Web Vitals (page speed, interactivity, visual stability), mobile-friendliness, HTTPS, intrusive interstitials (pop-ups).
Do searchers actually like this result? Signals (indirect): click-through rate, dwell time, pogo-sticking (clicking a result then bouncing back).
Google's AI-era ranking increasingly favors:
If you're starting: fix indexability first, nail relevance via search intent, then build authority, then optimize UX. In that order. Each layer compounds the ones below.