Is you or your client's websites not moving at all in google? Are the rankings swinging because you don't have enough power and authority link building? Have you done everything there is to do in terms of on-page and yet you can't compete with high link power websites taking up the whole front page?
All of the on-page resources you put into it with amazing content will never get seen if you don't start getting some organic visitors by sending amazing backlinks to your website.