>> It persists in many places due to the deeply ingrained belief that, for one reason or another, it would be technically, practically, or economically impossib

>> It persists in many places due to the deeply ingrained belief that, for one reason or another, it would be technically, practically, or economically impossible to migrate functionality off the mainframe. > It is never technical or pratical reasons, always economic reasons. To use contemporary vocabulary, you "just" need to replicate a "multi tenant HA cloud environment" to migrate from a mainframe at great cost. When your business processes are so ossified by a mainframe that you have, say, groups preparing Excel spreadsheets -- with data formatted from one mainframe screen in 3 columns -- for use by another group to input back into the mainframe -- with the data reformatted in 4 columns -- you know you're never escaping the gravity well of the black hole at the center of IT that is "The Mainframe." This is just how it's going to be until the company is so technically irrelevant that the remains are picked up in a fire sale by some PE to sell off to some other, tangentially-related company, solely for the IP assets.