Web Analytics and Internet Advertising
Web analytics is also valuable if you're purchasing advertising on the Internet, especially pay-per-click (PPC) advertising. You can track and analyze which campaigns result in the most conversions from clicks to actual sales. And if you're advertising on Google's AdWords, you can track which keywords are triggering the most ad displays and which ads have the highest click-through rate.
In other words, you can use web analytics to track the effectiveness of each ad you place. With proper analysis, you can learn which ads are driving the most potential customers and which ads aren't pulling their weight. That information will help you better place ads in your next campaign; you fine-tune your advertising strategy over time.
Without web analytics, you have no idea which ads are working and which aren't. You learn from both your successes and your failures.