For years, many IT organisations have managed perfectly well without being especially clear about what a "service" actually is. Not because the issue did not matter, but because it was easy to hide. You could run IT through projects, applications, infrastructure towers, support queues, and cost centres and still create the impression of control. There were systems to monitor, budgets to defend, incidents to resolve, and roadmaps to present. The machinery looked busy, and busy often passes for managed.