This garbage consists of: a) Web Spam
 , b) incorrectly identified death links (Soft-404 pages , parking pages); c) duplicate contents , etc.
The update was meant to attack web spam
and decrease the rankings of websites that did not meet Google's quality guidelines.
Link farms, content farms, article spinning and keyword stuffing are among the illegitimate endeavors, falling under the general category of web spam
(also called search engine spare, search spare, and spamdexing), to try to trick Google into directing you to sites that may meet your search needs or more likely are junk that at best wastes your time.
According to Tech Edu News, the head of web spam
at the California based organisation, Matt Cutts, has revealed that Google is looking into introducing a ranking update later this year, so that websites with poor levels of customer service and satisfaction don't appear higher in search engine results pages than rival sites with happy customers.
Google does not hate SEO nor does it hate SEO Companies; Google has said publicly that it cannot tolerate bad practice SEO and Web SPAM