A very good question, Todd!!!
All traffic is NOT created equal. There is “Traffic” and there is “QUALIFIED Traffic”. Do you know if your visitors are QUALIFIED already? If not, you can’t appropriately say they “should buy”, and you can’t make proper adjustments to your site until you know that.
As a sample illustration, let’s say you have a brick and mortar store you sell from on a “busy street”. You get a lot of “visitors” walking buy the store, BUT, a “Window shopper” is less qualified to buy, and probably will not. However, a person that actually walks into the brick and mortar store is more qualified and therefore more likely to buy from you. Make sense? It’s no different on the Internet.
You have to determine who is qualified and who is not (the difference on the internet is that just because a visitor “comes to your site” doesn’t mean they are qualified). You have to begin to qualify them from the first moment they come in contact with you. This could be through Organic SEO, Paid Search (PPC), or any number of other advertising means. It is also achieved through proper tracking and analysis.