Patch management strategy research paper

This research paper will focus on issues and concerns with Patch Management.  With the advent of many types of software and systems, patch management is major nightmare.  Patching the system may cause the system to crash, and not patching it can leave it vulnerable to attacks.  Please research the issues and concerns with patch management and provide your views on the topic. Please consider this at an enterprise level where the complexity is increased exponentially with the increase in the number of systems