You may very well already have Google Analytics installed. It's free, it's accurate and it's cool. Google lets anyone with a website measure their traffic and dozens of other metrics. The entire dashboard is focused on how many people come to your site, how many pages they view when they get there and how long they stay.
Given our desire to be popular combined with Google's desire to give users what they want, it's not surprising that traffic is the key driver of the program.
But traffic is a red herring. At best, it's distracting, a stand-in for something more useful. At worst, though, it's dangerous, because the quest for traffic causes you to make bad decisions.
Why do you have a site? What's your goal? Is it to sell something? To receive email? To spread an idea? Whatever it is, you can probably measure it. And measure it you should. Every other piece of Analytics data is trivial compared to that one number.
Short version: if you don't understand how to do goal tracking and funnel analysis, don't use Analytics until you do.
Google offers Analytics for a reason. They're not being selfless... they understand that efficient websites are more likely to buy traffic, because those sites can more easily convert traffic into revenue. The purpose of the program, then, isn't to stroke your ego (or make you feel inadequate). Instead, it's a tool to help you redesign your site every single day to make your ultimate efficiency go up.