Topical Authority
Topical authority measures how deep and consistent a site's content is on a given subject, in the eyes of search engines.
A site that covers a subject from multiple angles, with pages that reference and complement one another, reads as more trustworthy than a site with one isolated article on the same theme.
Building this authority takes time: it's earned article by article, around a consistent topic core, rather than by spreading effort across unrelated subjects.