While there’s a strong correlation between search results placement and clickthrough rates, ranking is not the supreme end goal that it used to be. Studies of click through rates and user behavior have shown that searchers favor the top search results -- particularly the top-three listings. However, it’s also been shown that on subsequent pages, being listed toward the top of the page shows similar click behavior. And with search results now being appended with rich text/snippets, results that appear below the top-three search results are getting much higher clickthrough rates.
Even before all of that was applied, rankings did not guarantee success. Theoretically, you could rank quite well for a term, get tons of traffic, and not make a dime from it. Is that what you really want? I don’t think so.