The imminent departure of Roger Ailes after 20 years as the boss and driving force of US cable network Fox News, and the £24bn bid for UK technology company Arm Holdings by Masayoshi Son’s SoftBank, are quite different incidents. But they have one quality in common: a founder’s reassertion of control over his business empire. Both events caused shocks this week but no one should really be surprised. If Mr Ailes’s ejection at the hands of Rupert Murdoch was a long time coming, the end was bound to come. Similarly, the notion that Mr Son would stop selecting investments himself and cede control of the business he founded in 1981 to Nikesh Arora, a former Alphabet senior executive, was far-fetched. Both SoftBank and Mr Murdoch’s empire, which now spans News Corp and 21st Century Fox, are family enterprises to their core. Their patriarchs are guiding spirits who take business decisions more on instinct and a sense of the future than hard data about the present. They invest in the faith that customers will eventually come. There has always been a place for outsiders at the companies: professional executives who are given responsibility for divisions or, in the case of SoftBank, the operations in which it acquires stakes. Essentially, though, they are risk-taking businesses in which the family exercises the final say.