I'm a noob webmaster myself and it doesn't take a genius to figured out why tubes are hated.
First it's free, they steal content and upload it on their sites, so ask yourself this: Would you rather pay for porn or watch it for free?
Secondly it's become proliferated, anyone can build a shit tube site, throw a bunch of shit videos, trade some shit traffic and make a couple of bucks. This is the reason why adult traffic has become a joke, because the 99.9% of the surfers are free-loaders so when they come across a paysite, they laugh their asses off and leave.
My advice, offer them something the tubes can't, and even then expect the conversion rates to remain low.
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