In the long arc of technology's most consequential companies, leadership transitions carry the weight of entire eras. This week, John Ternus assumed the chief executive role at Apple, bringing to Cupertino a reputation for quiet composure and deep institutional knowledge earned across years inside the company's product development core. He inherits not merely a title but a set of unresolved tensions — between hardware ambition and software readiness, between Apple's cautious tradition and the urgent pace of artificial intelligence — at a moment when the industry will not wait for anyone to fin