Unlike the stand-alone, isolated mainframe era, our applications today are interconnected. In an academic environment, perhaps the author didn't experience in

Unlike the stand-alone, isolated mainframe era, our applications today are interconnected. In an academic environment, perhaps the author didn't experience intersystem dependencies. In production environments, however, there was arguably more interdependency with (and, therefore, risk to) other systems and users. Take a manufacturing environment. Shop orders take in inventory information, labor detail, assembly progress, facilities and supplies usage, etc., any or all of which can involve independent systems. In turn, each production step can create information that needs to go back to each system. Any error or change in those inputs and outputs could force a rerun of all systems downstream of the first error. This is especially noteworthy to the guy/gal being called in at 3AM to unravel such hairballs. I'd daresay that most interconnection with external systems in the modern mobile environment is primarily used for social media, tracking and other privacy suckage. (Ghostery output can be quite surprising, for example.)