Search engine optimizers have learned tricks that change the search results that drive much of the traffic to successful websites. The tricks are called black-hat SEO, though that’s something of a misnomer since, as SEOs like to say, they don’t break the law, just the search companies’ terms of service. The tactics became so aggressive that the SEOs started to make the search engines look bad. Search companies tried to stay ahead of them by tweaking their algorithms and adding filters.”]
Source: https://www.csoonline.com/article/2122458/black-hat-seo–part-two–seown3d–1.html