As a product it clearly failed. It did not meet its sales numbers at all, they had to extend XP's life over and over and finally killed the gift horse so that V

As a product it clearly failed. It did not meet its sales numbers at all, they had to extend XP's life over and over and finally killed the gift horse so that Vista would be installed on machines by default. Many people would choose XP over Vista if they could on their machines. I think most people would reasonably call it a failure from a business perspective.