Suppose we look at a Web site as an argument. Think of it as "you" telling the world that you exist, you`re interesting, and you should be noticed---at least that`s what you`re arguing. Hopefully, you`re also suggesting (arguing) that you should get money from the world, and that you`re going to exchange something for that money that`s really, really cool. :-)
That`s your side the argument. The world basically says, "So?"
What`s the most basic thing you have in your argument? What`s the foundational premise that supports everything else on the site---that leads people to the conclusion that, yes, you do indeed have something interesting and cool?
This is a different way of asking what it is that you *offer* rather than what you`re doing. Lots of people put up a Web site. That`s what they`re doing. But they assume the site makes a complete and compelling "argument" in favor of getting someone *else* to do something.
For example, what`s the basic premise for Amazon.com? What`s the basic premise for Wikipedia, or for Startup Nation? Aren`t those examples instantly clear as to their bottom-line statement?
If you`re clear on that basic premise, then the next step is to go through each and every page on the site and examine how it supports that basic premise. How does it "stick to the point?" After that, the final step is to examine all the written content on the site, to see if it also supports that basic premise.