<b>"Two sites, same network, wildly different RPM — one's setup is broken"</b>

<b>"Two sites, same network, wildly different RPM — one's setup is broken"</b>

Maybe. But check the four boring variables first, because they explain most of it before any "broken" theory:

— Geo split (US share of <i>revenue</i>, not sessions)
— Niche CPM band (finance/insurance vs lifestyle is a 5x advertiser-demand gap)
— Device mix (desktop viewability beats mobile)
— Content length (word count drives ad slots that actually get seen)

🚩 Hidden variable: niche-level advertiser demand. A personal-finance site and a craft blog on the identical network and layout will never converge, because insurance buyers outbid yarn buyers by an order of magnitude.

Not saying setups never break — saying "same network, different RPM" is the expected result, not the anomaly, and people debug the install when they should check the niche.