There comes a time that a lot of Musk's ventures will fall to pieces. SpaceX may be a wonderful shot in the arm for space travel, a Mars mission is out of the question in the coming decades. Musk fans will grow impatient. Unless Musk comes up with something excitingly new and revolutionary ('autopilot' already tanked), Tesla will be facing strong competition from EV makers in China and Korea. Twitter is losing advertisers as well as subscribers.