While doing research on my upcoming book about running a successful Security Operations Center (SOC), I have interviewed people who have built and run SOC as well as survey reports from organizations like SANS and others. Overall it is a sorrow state of affairs where almost half of the organizations have no metrics for measuring the success of SOC implementations. The ones who have a metric, are mostly using non-business focused measurements to gauge performance of the SOC. Some are using metrics just to justify a particular technology investment.
Most of the people are not focusing on automation (doing manual work).
There is a lot of work that needs to be done to make a SOC efficient and real metrics to demonstrate business value!