Recently, Musk posted images to his Instagram account from the Gigafactory, including a picture and video of him and his colleagues roasting marshmallows and drinking whiskey on the roof at night. He explained on Twitter that camping atop the Gigafactory was faster than getting to a hotel in Reno, the nearest town of any size.

"I really believe that one should lead from the front lines and that's why I'm here."

"I always move my desk to wherever — well, I don't really have a desk, actually. I move myself to wherever the biggest problem is in Tesla," said Musk.

Musk was hosting the call from the Gigafactory, Tesla's battery production facility in Nevada, because that is where he has been working day and night to correct production delays, he said.

Elon Musk disappointed Wall Street investors in the most recent quarter and Tesla stock is taking a pummeling Thursday as a result. But during Tesla's earnings conference call with analysts on Wednesday, there was a notable theme: Musk presented himself as a leader who's out on the field alongside his employees.

Indeed, on Wednesday's call, Musk said he has been at the Gigafactory all hours of the night.

"I am personally on that line, in that machine, trying to solve problems personally where I can," Musk said. "We are working seven days a week to do it. And I have personally been here on zone 2 module line at 2:00 a.m. on a Sunday morning, helping diagnose robot calibration issues. So I'm doing everything I can."

In July, Musk predicted that getting the production of Tesla Model 3 ramped up would be "manufacturing hell." On Wednesday, he likened the experience to "Dante's Inferno," admitting that it was emotionally taxing.

"Let's say level nine is the worst, OK? Well, we were in level nine," he said. "I was really depressed about three or four weeks ago when I realized that we're kind of in level nine," he said. "I was sort of quite down in the dumps."

But things are looking up. "We're now in level eight and I think we're close to exiting level eight," said Musk. "Now I can see sort of a clear path to sunshine. So I feel really pretty optimistic right now."

It's not the first time Musk has publicly talked about his roller coaster of emotions. At the end of July, Musk said the reality of being a successful, high-profile tech CEO is "great highs, terrible lows and unrelenting stress."

The recent stress of Tesla's production schedule for the Model 3 falling behind (much to the dismay of analysts) is partially because a key subcontractor did not deliver as expected. Musk said on the call that he and his team were putting in overtime work to correct the miss. However, it's not the first time Tesla has missed production estimates. Musk has a history of setting projections the company then doesn't meet.

In any case, "[A]t the end of the day, everything is our fault – and my fault most of all," admitted Musk. "If we pick the wrong subcontractor, we're the fault. So, I don't want to just be externalizing responsibility."

Musk's stories about working long hours, elbow to elbow with his employees may be in part a strategy to mollify investors unhappy with Tesla's missed targets. But it's also is a smart leadership move.

Research has found that the top positive influence on a typical worker's level of job satisfaction is bosses who have the technical skill set to complete the work they ask their subordinates to do.

Among American workers, "it's considerably more important for employee job satisfaction than their salary (even when pay is really high)," the authors of the research told the Harvard Business Review. The study focused on 35,000 randomly selected employees and workplaces in the U.S. and Britain.

Musk showing his emotional side is also important when it comes to leadership. Legendary Starbucks CEO Howard Schultz has espoused its value.

"I think the leader today has to demonstrate both transparency and vulnerability, and with that comes truthfulness and humility and obviously the ability to instill confidence in people, and not through some top-down hierarchical approach," he said in an interview with the Harvard Business Review.

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