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

https://www.deltabookmarks.win/tiered-link-building-helps-scale-your-authority-without-overspending-by

Tiered link building uses two levels of links to improve your site’s ranking. Tier 1 links point directly to your site and are high-quality. Tier 2 links support those Tier 1 links to boost their power