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

https://wiki-club.win/index.php/What_Should_I_Say_in_a_Broken_Link_Outreach_Email_to_Get_a_Yes%3F

Tiered link building uses two levels of backlinks to boost your site’s ranking. Tier 1 links point directly to your main site, giving it strong, direct value. Tier 2 links support those Tier 1 links, making them stronger and more effective