Code is not an asset – it’s a liability. The longer a computer system has been running, the more tech debt it represents. The more important the system is, the harder it is to bring down and completely redo. Instead, new layers of code are slathered atop of it, and wherever the layers of code meet, there are fissures in which these systems behave in ways that don’t exactly match up. Worse still: when two companies are merged, their seamed, fissured IT systems are smashed together, so that now there are adjacent sources of tech debt, as well as upstream and downstream cracks: