There happen to be different approaches to talent recruitment, but Uber’s is unique. Its CEO Travis Kalanick wanted to recruit a top notch CTO and thus did not want to leave anything to chance. He thus interviewed the candidate Thuan Pham for thirty hours across two full weeks. On further discussion with Pham, it was understood that beyond interview, these sessions where in fact business meetings. In fact, in order to grow Uber, Kalanick wanted to brainstorm with someone who was very different to him and provided differing viewpoints.

Source: http://www.businessinsider.in/Uber-CEO-Travis-Kalanick-spent-30-hours-quizzing-a-candidate-before-finally-offering-him-a-job/articleshow/51674093.cms