Google's entire (initial) claim-to-fame was "PageRank", referring both to the ranking of pages and co-founder Larry Page, which strongly prioritised a relevance attribute over raw keyword findings (which then-popular alternatives such as Alta Vista, Yahoo, AskJeeves, Lycos, Infoseek, HotBot, etc., relied on, or the rather more notorious paid-rankings schemes in which SERP order was effectively sold). When it was first introduced, Google Web Search was absolutely worlds ahead of any competition. I remember this well having used them previously and adopted Google quite early (1998/99).

Even with PageRank result prioritisation is highly subject to gaming. Raw keyword search is far more so (keyword stuffing and other shenanigans), moreso as any given search engine begins to become popular and catch the attention of publishers.

Google now applies other additional ordering factors as well. And of course has come to dominate SERP results with paid, advertised, listings, which are all but impossible to discern from "organic" search results.

(I've not used Google Web Search as my primary tool for well over a decade, and probably only run a few searches per month. DDG is my primary, though I'll look at a few others including Kagi and Marginalia, though those rarely.)

<https://en.wikipedia.org/wiki/PageRank>

"The anatomy of a large-scale hypertextual Web search engine" (1998) <http://infolab.stanford.edu/pub/papers/google.pdf> (PDF)

Early (1990s) search engines: <https://en.wikipedia.org/wiki/Search_engine#1990s:_Birth_of_...>.