What pieces are you missing?
It's important to realize in your Patch Management process, that "hitting the deploy" button, is not enough. In the majority of the companies I interact with, the IT department is patching, but just barely.
Taking a much broader view of security in your infrastructure is vital now more than ever. Today's CISO is still looking at the AV, DLP, Network stance for security, and are missing on the possibly thousands of software issues that are in the endpoints, and servers.
ITS Managed Services has identified the key outcomes in order to mature, and have a better than 98% compliance rate in Patch Management.