Google works with more than 10 thousand search quality raters from all over the world. They are real people who evaluate search results, rating the quality of pages that show up at the top for given queries. To do their job, they use the search quality rater guidelines.
These guidelines tell quality raters in great detail the aspects they should take into account when assessing a page.
The guidelines are about 200 pages long and contain information about the type of pages to be examined and how to evaluate them. The document includes the characteristics low and high-quality pages should have, examples of each, and more.
The goal of quality raters is to determine whether the results they check meet the needs of searchers. However, they don’t alter Google’s results directly. The data obtained through this process is used to improve how algorithms and indexing work.