Internet sales and much more
Because real spam merchants are excellent at showing search engines what they want to see, search engines constantly revise their algorithms, changing their "opinion" of overused SEO tricks. Google is particularly frustrating to target; site features that Google loved three years ago might now be verboten. If your SEO knowledge is too old or your SEO tool is calibrated for a previous algorithm, whoosh, down goes your page ranking. As you can see, online SEO tools might seem to be an easy and economical way to optimize your site yourself, but you could find that you have been penny wise and pound foolish. A better alternative to doing your optimization yourself, then running an ad campaign to fix the damage you might do, is to invest in a professional seo services firm.