[CDarklock]

Let me point out another reason people register and don't post.

Because you MAKE THEM.

Yesterday, I went to a site about nutrition and bodybuilding. I clicked the "About Us" link. It said "Sorry, you must be signed in to do that!"

So I registered, because I wanted to see if this company was one worthy of my business. And it wasn't (which is why I won't say who it is). So I left, and I won't go back, which means I'll never post.

Keep in mind that this isn't always an intentional feature of the site. The example above is, but it's also possible that some brilliant post in your forum was crossposted elsewhere by a member, and people are having to register so they can see it.

Oh, and also: what ablaye said.