In October 2003, just one year after founding SpaceX, Elon Musk spoke at Stanford about why he entered the rocket business.
At the time, almost no one believed a private company could succeed in orbital launch.
He later said he gave SpaceX less than a 10% chance of succeeding — but felt it was still worth trying, because without a new entrant, humanity might never become multiplanetary.
20+ years later, SpaceX became the dominant launch provider and the first private company to fly astronauts to the ISS.
Source: Stanford Entrepreneurial Thought Leaders lecture, Oct 8, 2003