why the link building method is the most effective way

I wonder why the link building method is the most effective way
If only Tier 1 posts are linked to the Moneysite, and if Tier 2 and Tier 3 are linked, then is Tier 1 just focused on good indexing? And how is the DR index affected? For example, even though many backlinks are built, the DR index remains the same. Some sites have drastically increased DR indexes with the same work.
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Why you care about DR which is pretty simple to manipulate and don't have any influence on Google ranking ?
If you'll choose great expiring domain for PBN, you already have all tiers done.
DR is not that important. It has no direct correlation with SERP
Why? Why complicate a simple thing, Create the first tier 1 get it index and blast it with other links (Not a complete spam).
add the high DA and niche related sites with good TF.
If only Tier 1 posts are linked to the Moneysite, and if Tier 2 and Tier 3 are linked, then is Tier 1 just focused on good indexing? And how is the DR index affected? For example, even though many backlinks are built, the DR index remains the same. Some sites have drastically increased DR indexes with the same work.
Do check the quality and strength of backlink. If its high and authority backlinks it will not affect your sites.
Don't get caught up on metrics like DR. They can easily be manipulated

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