Originally Posted by harvey

simply because you're playing with surfer's fantasy. When you show screencaps the viewer will try to connect the screencaps to a story or fantasy, which will be always pleasant. It's known as "law of closure", a basic principle of the Gestalt psychology theory: you try to complete the elements that are missing. In this case, the story going behind the pictures, the sex scene, the moaning, the screaming, whatever.

In a video, that fantasy is turned off and you see what it really is, and no matter what, it will always be worst than your ideal scene. That's why no preview tours works better than preview tours. Personally, I never, ever, ever saw a tour with previews converting better than a tour for the same site with no previews. If you choose the correct thumbs and screencaps (that means: following a logical story), your conversions can be 10x better easily. Of course, this alone won't guarantee success, there are many elements to keep in mind, but it's something to keep in mind nevertheless

This being said, I'm always asked to do tours with video previews. And I always tell people what I said above, but well, 90% of webmasters prefers preview no matter what, so I have to include previews. Plus, most webmasters don't use/like alternative testing tours, when you could easily have exactly the same tour, one with previews, one with the same preview going to join page. As easy as that.

Finally, we have the join page. If you're weak on your tour, you better have an amazing join page to balance the leaks in the tour.

For most adult webmasters, join page is an end instead of another step, namely, the most important of all the pages. So you see join pages which are just form holders, or a form and some screencaps. With that, you already cut at least 50% of sales. Period. When you see 100 people hit the join page (talking about tours with no blind links to join, ie tours with previews) and it converted to 1 or 2 sales, then you know something is extremely wrong. Either the program is shaving like mad, either the join page is a failure by definition. However, I rarely saw any webmaster worried about the most important page in the site. Gee, I've saw people more interested in warning pages than join pages (for real)