Amazon's cloud business records 18% growth in second quarter Far removed from its days as an experimental clean-tech startup led by a member of the "PayPal mafia," Tesla is now the eighth most-valuable publicly traded U.S. company, with a market cap of over $1 trillion after nearly hitting $100 billion in revenue last year. The Roadster is largely in the history books, and the Model S is no longer of great importance to the company's bottom line. Rather, it's Tesla's top-selling Model Y SUV and Model 3 sedan, along with sales of environmental regulatory credits, that helped define the company's financial success over the past decade. But for the 54-year-old Musk (his birthday was Saturday), now the world's wealthiest person, that's the past. He's told investors that the reason to buy and own Tesla stock from here has almost nothing to do with selling cars to consumers. "If somebody doesn't believe Tesla's going to solve autonomy, I think they should not be an investor in the company," Musk said on an earnings call in April of last year. He added, "We will, and we are." Two months after that, Musk said his company's Optimus humanoid robots that he hopes some day will perform like R2-D2 and C-3PO in Star Wars, could some day lift Tesla's market cap to $25 trillion. Musk, who last year characterized himself as "pathologically optimistic," has said he expects thousands of Optimus robots to be working in Tesla factories by the end of 2025, and that the company will begin selling the robot next year. As for autonomy, Tesla currently lags behind Alphabet's Waymo, which is operating public robotaxi services in several U.S. markets, and Baidu's Apollo Go in China. Tesla's Robotaxi just launched a very limited pilot service in Austin, Texas, earlier this month, and said Friday it had completed its first driverless delivery of a new car to a customer. While Tesla still has its share of fanatics and a largely bullish slate of analysts, Wall Street is skeptical of Musk's futuristic promises or sees them as baked into the stock price. The stock is down about 20% this year, badly underperforming major U.S. indexes and trailing all of its megacap tech peers. Apple, down 19.7% for the year, is the only one close. Earlier in June, Tesla's vice president of Optimus robotics, Milan Kovac, said he's leaving the company after a nine-year tenure, and Musk more recently fired Omead Afshar, the automaker's vice president of manufacturing and operations. Meanwhile, Tesla EV sales have been sluggish in 2025, with automotive revenue suffering a second straight year-over-year decline in the first quarter due to an aging lineup and bustling competition, especially from lower-cost Chinese manufacturers. New Tesla sales in Europe fell for a fifth straight month in May, according to data from the European Automobile Manufacturers Association, or ACEA, and Tesla's newest model, the Cybertruck, has failed to gain significant traction in the U.S. after a series of recalls. Hovering over Tesla's business is the unpredictability of Musk. Long glorified for his business success — through PayPal, Tesla, SpaceX, brain tech startup Neuralink and artificial intelligence company xAI, among other pursuits — Musk asserted himself in the political realm last year, when he endorsed Donald Trump for president and subsequently injected nearly $300 million into his campaign and related Republican causes. Kevin Dietsch | Getty Images Tesla CEO Elon Musk holds a key gifted by U.S. President Donald Trump in the Oval Office of the White House on May 30, 2025 in Washington, DC. Musk spent the first few months of 2025 spearheading President Trump's Department of Government Efficiency (DOGE), slashing the size of the federal government and stripping resources from regulatory agencies, including those tasked with oversight of his companies. But his pivot to politics came at a cost, at least in the short term. Musk's vocal and financial support of Trump, endorsement of Germany's far-right AfD party and extended string of charged and divisive remarks and gestures, including on his social network X and in press appearances, has been correlated with declines in Tesla's reputation, and a drop in his overall favorability, according to polling data. "Unless Tesla can come up with a whole range of new products that will really excite consumers, and unless they can mitigate some of the antagonism caused by their leader, they will be seen as past their peak and will begin to go down," David Haigh, CEO of research and consulting firm Brand Finance, said in January. Brand Finance's data showed that the value of Tesla's brand fell by 26% in 2024, a second straight annual decline. That was before Musk's time working in the second Trump administration. Musk's official tenure in Washington, D.C., ended earlier in June, just as his relationship with the president was souring. Shares of Tesla fell 14% on June 5, as President Trump threatened to pull government contracts for Musk's companies, escalating a war of words over the president's spending bill. Musk temporarily slowed his posting about politics on social media after that, and appeared to focus more on promoting his businesses. But this weekend he resumed attacking portions of the bill that would hamper solar and renewable energy companies, including Tesla. Whether Musk is now focused enough to solve Tesla's problems and, even if he is, whether that's a big catalyst for the company, is very much up in the air. Musk and Tesla didn't respond to a request for comment. Tesla investors have learned that volatility is a big part of the story, and has been since the company's stock market debut. On more than 40 occasions in the past 15 years, Tesla's stock has gained or lost at least 20% in a single month. Here are the three best and worst months for the stock and what happened to cause these hefty moves: The good months