IE tends to get the most of the fixes in Patch Tuesday not necessarily because it is inherently more buggy than other Microsoft software, but because it is widely used software that could provide an entry point for outsiders to break into the computers that run the browser. As a result, it is under such scrutiny by both malicious attackers and security researchers.
IE is not necessarily any more buggy than other popular browsers, such as Google Chrome or Mozilla's Firefox. Both Google and Mozilla have automatic updates for their browsers, so a vulnerability can get addressed as soon as the developers create a patch to fix the problem, noted Amol Sarwate, the director of Qualys' Vulnerability Labs. As a result, such bugs and their attendant fixes are rarely called out in the press, unless they are critical in nature.