Interesting how this might be confined to tech, due to the shorter product cycles. Case in point: Richard Branson and Virgin's empire. Technically, they're (Virgin Group) a branded vc firm, but Branson himself is a chairman, not a CEO, and I believe that he wasn't the CEO for the companies that he started either (the name Nik Powell rings a bell.)
Taken as such, perhaps it's not that hired CEOs are useless intrinsically(as the tech world loves to believe) but merely are good at operating in existing industries (Virgin Records wasn't the first record company, Virgin Atlantic wasn't the first airline, etc.)