For how long did the businessuse the seo company? 

Many of the clients that attend my SEO training courses have previously had a bad experience with SEO companies that they hired to improve their visibility on Google. In conjunction with CINT we surveyed 1000 business owners (with fewer than 100 employees) who used an external SEO company for their company’s website to see how they felt about the service they received.

http://www.seotraininglondon.org/bad-seo-killing-small-businesses/