Search engines like Google crawl the web, index the pages they find, and then rank them for each query. SEO lines your site up with how that pipeline works. If a page can't be crawled, it can't rank. If it can be crawled but doesn't clearly answer the query, it ranks low.
None of this is a one-time task. Competitors publish, Google updates its systems, and search behavior shifts. SEO is closer to ongoing gardening than to a single project you finish and walk away from.
Updated July 2026
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