Google Analytics will track only visitors with browsers. It won't tracks hits made by all kind of bots that do not execute JavaScript. This is good if you want to see real surfers in your stats. Average website gets about 20 hits a day from bots.
If you are serious about stats I recommend you check out
www.gashortcut.com brochure.
If you want more advanced webstatistics that will track bot hits, try
CNStats. This is PHP software for stats tracking and analysis.