I think it is because most sysadmins didn't study computer science in school, and don't know much about software lifecycle management. When you have a big comp

I think it is because most sysadmins didn't study computer science in school, and don't know much about software lifecycle management. When you have a big complex environment with thousands of servers all running the same code, it makes sense to start treating the hardware itself like software components. All modifications to hardware can be committed to a central SVN repository and pushed out with post-commit scripts. As long as you can script all types of OS patches, firmware updates, etc, using some type of language and an automation tool like Puppet or Cfengine, this can be done. For a large company like Google or any cloud provider I'm sure it makes sense to start treating your server infrastructure like software components and have the same type of change control, QA, and deployment methodologies wrapped around it.