Here is another video from Maile Ohye of Google talking about common mistakes in SEO that lead to undefined path and that is having no rank at all. SEO is not just about link building it must coordinate with a business marketing efforts in order to gain its business goal and objectives.
Although this are just five common mistakes but I tell you this is much of help. You will surely see that their might be something in your SEO why your client’s business cannot met its goal. And at the end it is only reminding us that website of our client is the gateway of their business and therefore coordination with their marketing efforts and our SEO techniques are truly essential.