While Eberhard and Tarpenning laid the groundwork, Elon Musk's significant investment and eventual leadership dramatically shaped the company's trajectory. He joined the board in 2004 and became the CEO in 2008, bringing considerable funding and a visionary perspective that focused on mass production and a broader market reach, ultimately transforming Tesla into the globally recognized electric vehicle giant it is today. Therefore, while the company's origin lies with Eberhard and Tarpenning's vision, Musk's involvement was crucial in its evolution and success.