Both Apple and Microsoft only update their browswers with a new OS.Safari and IE are actually good when they first come out but after a few months or so other browsers seem to outperform or/and be more compatible with the latest technologies(like HTML5).Some of you may say that they do but these are usually small updates to fix problems or improve security but not performance or compatability.The reason I came up with this question is because safari and IE may often not work with some pages that use newer technologies or perform worse in comparison with other browsers in specific pages(in comparison with other browsers like Firefox,Chrome,Opera etc)