Why cutting disability benefits will be a nightmare for the government

Even though we live in a welfare state i still think people should have more responsability over them selfs, even though they are disabled, which they have no controll over. Now this obviously triggers some people and it's abvoius that people that ACTUALLY can't physically work can't work thus in a welfare state we should still keep them alive, but what really triggers me is the title. Cutting disability benefits won't be a nightmare for the government AT ALL! UK is not a charity!