What was the reason behind Penguin Update: Google is world’s famous search engine and Google wants to show exact results to their users against their search. I think on large scale Google has caught many spammers because where a 10th or 12th pass out person can do SEO with the strategies like data work. Now Google is not giving any kind of importance to this kind of work which is related to specially bulk submission to create numbers of back links in less time.
What is the bulk Submission: After Penguin 2.0 update numbers of SEO companies has been shut down because they were not working according to perfect SEO guidelines. What they exactly did they were taking less money than other experienced SEO services provider and build numbers of back links in less time with directory and bookmarking submission which was totally low quality back links. What was in earlier age of SEO the site will rank quickly which will have more back links. The website was ranking in SERP with in the time period of 1 month from above those all websites which were using white hat SEO techniques. This was the main reason why Google decided to launch Penguin update to control black hat SEO activities.