System administration can be a rather conservative profession. ("If it ain't broke, don't fix it.") Worse, some system administrators suffer from an attitude problem. Perhaps they perceive themselves as undervalued by colleagues, like a kind of digital janitor. Perhaps they're reluctant to share what they know, for fear of making themselves dispensable. Perhaps they're simply so overloaded with time-consuming work that their default response is "Go away!"
This can lead to "BOFH": the system administrator as remote, unfriendly, inaccessible, enforcing unhelpful and bureaucratic policies, rejecting new ideas. The last person, in fact, you'd want to ask for help with a problem.
Automation tools such as Puppet are a threat to this kind of sysadmin, because she sees herself as the guardian of the secret technical information about how the systems work. "Why, if all that information was in Puppet, everyone would be able to see and understand it, and they could build and manage their own...