Tesla will hold its second-quarter earnings call with shareholders and analysts today. It's an important one, though that's nothing new for a company that's faced mounting skepticism for the past year-plus.

What makes this call extra critical is Elon Musk himself. The way he behaves could be a good indicator of what's to come from the CEO: either a renewed focus on leading the company like a professional, or more of the increasingly erratic behavior he's shown over the past several months.

Musk was combative during the company's first-quarter call in May, cutting off analysts' "boring" questions about the company's financials to focus on more interesting ones from a YouTube vlogger. Yes, the questions--which hit on driverless technology and future car models instead of current profit margins--were more colorful. But an earnings call, by definition, is about the company's financials. It doubles as a way of keeping CEOs accountable. Musk made it clear that, in that moment, he had little interest in taking those things very seriously.

The whole ordeal was a bit embarrassing, and Tesla's stock fell by 7.5 percent by the next day. Looking back, it also served as a precursor of what was to come from the CEO. Over the next three three months, Musk allegedly called and threatened the employer of a blogger who was critical of Tesla. He tweeted about drinking on Ambien. And perhaps most egregiously, he implied that a British diver helping with the Thailand cave rescue is a pedophile

All of those distractions overshadowed the fact that Tesla actually hit an important milestone in the second quarter: It manufactured 5,000 Model 3s in a week, a goal that Musk has been hyping as a major benchmark for nearly a year. 

Musk's reputation is critical to the success of Tesla. The company has a market cap larger than Ford's and nearly equal to that of GM's despite selling just 100,000 vehicles last year. (Ford sold 2.6 million; GM, 10 million.) Investors and shareholders buy into Tesla largely because they believe in Musk and the company's long-term potential. The company, after all, is yet to turn an annual profit. Trust is currency at Tesla.

Musk is rapidly eroding that trust. James Anderson, a partner at Baillie Gifford, Tesla's fourth-largest shareholder, might have said it best, telling The Guardian after the Thailand incident that Tesla's progress is "being overshadowed and undermined by this saga" and that what he really wants to see from the company is "peace, quiet, and execution." 

If Musk wants to pursue side projects like flamethrowers and surfboards, that's his prerogative. For better or worse, they're part of the quirkiness that has helped transform the entrepreneur into his own brand and build a passionate cult following.

But when it comes to leading his companies, Musk needs to be able to turn off the zaniness and turn on the seriousness. This doesn't necessarily mean working harder--Tesla has already run into plenty of issues surrounding how hard it drives its employees. It means Musk himself showing thick skin, sound decision-making, and an ability to drown out the distractions and focus on the real goals. He can use Wednesday's call to show that he can be levelheaded during trying times and handle criticism without lashing out.

If he doesn't, one thing will be clear: Musk hasn't learned his lesson yet. And if that's the case, he won't be the only target of Tesla's increasingly wary stockholders' wrath. 

Producing cars and batteries that reduce humans' reliance on fossil fuels is Tesla's mission. Anything that doesn't move the company toward that goal is just noise. Soon enough, that noise might drown out everything else.