A prominent argument in the politicisation literature links the degree of politicisation of international institutions to the extent of their delegated political authority. I criticise the authority-politicisation thesis as theoretically myopic and falling short of adequately explaining many empirically observable instances of politicisation. Instead, I argue that politicisation is driven by the (expected) consequences of particular governance arrangements and that the perceived significance and magnitude of such consequences need not correlate with formally delegated or recognised authority. I illustrate the argument with discussions of three types of institutions—the UN General Assembly, the G7/8/20 summits, and coalitions of the willing—each of which can be factually consequential and has triggered substantial politicisation without possessing, as an institution, much recognised political authority in its own right.