As soon as you have to create clusters and do not use a single machine, or use network drives/windows fs for data at rest in a usable way (not slow as hell), or

As soon as you have to create clusters and do not use a single machine, or use network drives/windows fs for data at rest in a usable way (not slow as hell), or do anything with the network that also has to be sightly secure, you really have to be an expert to do anything (securely). Windows Sec/Ops are probably the software engineers I respect the most.