It is given and always reminded by Google to provide unique and good content to share to our target audience but it is not always followed and at the end of the day, our Off-page submissions are being duplicated if we use the same content on two different submission sites.
Therefore, it is important to keep in mind that we should only submit our URL once on a particular website. We need to avoid duplication of our submission in web directory submission, social bookmarking websites and article directory submission. There are many good and reputable websites on the internet and we should not only stick with the common ones.
It is one of the hardest tasks to accomplish but we will get good results out of the effort and dedication that we will spend doing our off-page link building strategy. As Google always remind, we need to practice white-hat-seo avoid our website to be penalized and in order to keep up with their algorithm changes and updates, we should respect and follow their rules and guidelines.