I'm currently promoting the top tattoo program on clickbank. I'm sending traffic like crazy, about 1000 a day, mostly females and targeted audience from a popular topless males website but it doesn't convert at all. Not a single sale in week. How can such a product have a Gravity of 160? Something fishy?
I tried to get into that niche about a year ago and i couldn't get any sales either... I figured out that since the product i decided to promote had a good gravity and that there was tons of cheap keywords available it would be easy...
I'd say that most people hitting sites for tattoo's are only looking for ideas and not to actually buy anything. I see the same trend on one of my sites.