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

https://www.bright-bookmarks.win/stop-wasting-outreach-efforts-tiered-link-building-pushes-authority-from-tier

Tiered link building uses two levels of backlinks to boost your site’s authority. Tier 1 links point directly to your site and carry the most value. Tier 2 links support Tier 1 by linking to those backlinks, increasing their strength