Popular SEO research agency found that 60-70% of the content present online is copied, duped or comes under plagiarism. Although search engine doesn't punish you with any penalty, it doesn't mean you can copy as it without any ethics. Bloggers main job is to supply unique and fresh content, which will get huge appreciation by audience. There are few common mistakes while doing on page optimization such as writing h1 tag multiple times, plagiarism, weak primary conclusion, improper research about topic, lack of bonding between paragraphs. Share your views on the same question.