Tiered link building uses two levels of links to boost your site’s ranking....

https://www.apu-bookmarks.win/this-article-explains-how-tiered-link-building-works-by-using-tier-1-links-to

Tiered link building uses two levels of links to boost your site’s ranking. Tier 1 links point directly to your site from relevant, high-quality sources. Tier 2 links support those Tier 1 links, helping them gain authority and improve their impact