The "call to enter" model
 

I talking about this sites in which you can enter only if you can a surtaxed phone number. I'm trying to understand when it is a good idea to use this model.

I explain:

with the tgp model:
you send your galleries to websites, they list you, and you get traffic.
Statistically you have 1 chance on 1000 to get a customer, and with a good retention, the saler can win $20 * 3 months= $60 per customer (no affiliate here).

With the call to enter model: you have 100 users on your preview page, and on this 100 user you have 1 customer. So 1 chance on 100 to get a customer instead of 1 chance on 1000 !

The problem: for 1000 people with the tgp + paysite model: i win $60.
And for 1000 people wih the "pay to enter" model (micropayment) you win $1x10= $10 !
Of course you get more customers because of the price ($1 instead of $20)
But you have choisen the call-to-enter model because you have less content on your website (so no retention here).

So how to make a correct amount of money with the call-to-enter ?

you win???