This scenario occurs when a number of pages in a single website are in competition with one another on search engine results pages. This can cause issues, which include reduced page authority and lower conversion rates. This is also another sign of a poor quality website, and requires optimization.
Sean Si is a Filipino motivational speaker and a Leadership Speaker in the Philippines. He is the head honcho and editor-in-chief of SEO Hacker. He does SEO Services for companies in the Philippines and Abroad. Connect with him at Facebook, LinkedIn or Twitter. Check out his new project, Aquascape Philippines