This article breaks down how tiered link building works by using Tier 1 links...

https://andressbrilliantperspectives.huicopper.com/will-too-many-low-quality-backlinks-hurt-my-site-on-google

This article breaks down how tiered link building works by using Tier 1 links to boost your main site’s authority and Tier 2 links to support those Tier 1 pages