The running rate at which the website gets load is very crucial. It also impacts look for engine's positions because google things to serve most appropriate material or information to its customers in smallest time possible. Providing hyperlinks of the sites that are slowly is not a wise decision and so fast running sites are rated on top by google.
Please visit; http://grupo.unavirtual.una.ac.cr/unagora/blog/view/12820/use-joomla-cms-development-for-better-speed-and-performance