What Yoast does, and why it became the default
Yoast handles the things WordPress leaves undone: control over the title tag and meta description Google shows, an XML sitemap that stays current, core structured data, and a content analysis panel under every post. It has done those things for long enough that "install Yoast" became reflex advice in the WordPress world.
Its defining characteristic is caution. Yoast ships fewer switches than its main rival, documents what it does exhaustively, and errs toward safe defaults. For someone who does not want to make twenty configuration decisions before publishing, that is a genuine feature rather than a limitation.
The readability analysis is the underrated part
Most discussion of Yoast focuses on the green light for keyword optimisation. The readability panel beside it is quietly more valuable: it flags sentences that run too long, paragraphs that have become walls, missing subheadings, and passive constructions. None of that is a ranking factor directly, and all of it affects whether a reader stays.
The keyword analysis is cruder. It wants the exact phrase in the title, a heading, the first paragraph, the URL and the meta description. Sensible as a checklist, damaging as a target. Get to green and stop.

