Try to get to the point on the first page, or at least give people an idea of what your site is about. If people have to go hunting, they may move on.
There is nothing more aggravating than a site that forces you to navigate for ten minutes before even figuring out what they do, let alone offering you the information you’re looking for. Remember, if somebody is visiting your site, they are probably looking for something…try to make it easy for them to find it. Ask yourself what things people might be looking for in general, and try to make those things accessible easily from the main page.
If possible, try to also offer a way of searching your site, or at least contacting somebody if they don’t find what they’re looking for. Make sure that visitors don’t have to wade through endless links to get somewhere, and conversely, make sure they don’t have to scroll down thirty screens worth to find what they want.
Keep in mind that a frustrated visitor probably won’t be a visitor for long.