Whenever one of Musk’s engineers cited “a requirement” as a reason for doing something, Walter Isaacson explains (in his biography of Elon), Musk would grill them:
Who made that requirement? And answering “The military” or “The legal department” was not good enough. Musk would insist that they know the name of the actual person who made the requirement. “We would talk about how we were going to qualify an engine or certify a fuel tank, and he would ask, ‘Why do we have to do that?’ ” says Tim Buzza, a refugee from Boeing who would become SpaceX’s vice president of launch and testing. “And we would say, ‘There is a military specification that says it’s a requirement.’ And he’d reply, ‘Who wrote that? Why does it make sense?’ ” All requirements should be treated as recommendations, he repeatedly instructed. The only immutable ones were those decreed by the laws of physics.
When Mueller was working on the Merlin engines, he presented an aggressive schedule for completing one of the versions. It wasn’t aggressive enough for Musk. “How the fuck can it take so long?” he asked. “This is stupid. Cut it in half.”
Mueller balked. “You can’t just take a schedule that we already cut in half and then cut it in half again,” he said. Musk looked at him coldly and told him to stay behind after the meeting. When they were alone, he asked Mueller whether he wanted to remain in charge of engines. When Mueller said he did, Musk replied, “Then when I ask for something, you fucking give it to me.”
Mueller agreed and arbitrarily cut the schedule in half. “And guess what?” he says. “We ended up developing it in about the time that we had put in that original schedule.” Sometimes Musk’s insane schedules produced the impossible, sometimes they didn’t. “I learned never to tell him no,” Mueller says. “Just say you’re going to try, then later explain why if it doesn’t work out.”
[…]
The sense of urgency was good for its own sake. It made his engineers engage in first-principles thinking. But as Mueller points out, it was also corrosive. “If you set an aggressive schedule that people think they might be able to make, they will try to put out extra effort,” he says. “But if you give them a schedule that’s physically impossible, engineers aren’t stupid. You’ve demoralized them. It’s Elon’s biggest weakness.”
Steve Jobs did something similar. His colleagues called it his reality-distortion field. He set unrealistic deadlines, and when people balked, he would stare at them without blinking and say, “Don’t be afraid, you can do it.” Although the practice demoralized people, they ended up accomplishing things that other companies couldn’t. “Even though we failed to meet most schedules or cost targets that Elon laid out, we still beat all of our peers,” Mueller admits. “We developed the lowest-cost, most awesome rockets in history, and we would end up feeling pretty good about it, even if Dad wasn’t always happy with us.”