Do you know how people think when searching with Google? You should know, you probably reached this post using a search engine. Somebody put some comments inside an image to illustrate a very common way to think: people have no patience to see the results from pages greater than 3. Some stop at the end of the first page.
I am sure you think the same way, only on occasion you reach the fifth or sixth page, almost never on tenth page. So, do you really think that you don't need a SEO expert for your web project?