These people know the basics and at the same time they make very basic mistakes like pick wrong keywords, have no idea of landing page is, get involved with companies that offer Google ranking in 24 hours, etc.. (searchmarketingstandard.com)
So if your AdWords campaigns are running at a 3X multiple, the easiest way to get to a 5X or better multiple is to stop wasting money on the wrong keywords. (entrepreneur.com)
Probably the biggest mistake people make when doing their own PPC advertising is choosing the wrong keywords just because they want to get traffic. (iacquire.com)