Mostly five raters indenpendently rate the same task and are randomly chosen from a pool. This should reduce SQR conspiracies to near zero. Also, afaik, google

Mostly five raters indenpendently rate the same task and are randomly chosen from a pool. This should reduce SQR conspiracies to near zero. Also, afaik, google engineers use the SQR Feedback to enhance algorithms (example: spam detection) Second: In my active time - long ago - white text was still a thing to make keyword stuffing "invisible". As a result of the SQRs work (and maybe a lot of complaints about bad search results ;-D), the next revision of search ranking "killed" that method - at least for some time - for all pages and not only the rated ones (which were only a sample of all in existance).