imagine a site has 100 backlinks.

Your logic is:

1 + 1 + 1 + 1 ..... + (N) = 100

Google's logic is more like:

for keyword xxxxxxx:

1 + 0 + 0 + 1 + 1 + 0 + 0 .... (N) = 32


That's the anchor texts making some links not count.

It's more complicated than this of course, but in this simple visualization it should be clear.

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