Some people have some incorrect ideas about life and people.
Some people think that an entrepreneur is about starting a business, putting up the risk and hiring employees.
Some think highly successful (by your definition) people don't have as many challenges as "regular" people.
Those people are wrong. Very wrong. Because they're asking the wrong questions (thinking is nothing an ongoing internal Q&A) and looking at the wrong things.
How one deals with fear & uncertainty paints a highly correlated picture of where that person is and will be in life. Athlete, entrepreneur, parent, whoever. You too.
Fear and uncertainty are not choosy: they visit everyone from time to time. Everyone has doubts. Everyone questions themselves. Everyone has times they're not sure of a decision. Fear and uncertainty knock on every door.
The difference in people is in what you do when they knock.
Let them in, give them something to drink, fix them a hot meal, and have a long conversation -- maybe they can even move in! You have that exact room you're only using as an office.
Talk briefly at the door and schedule a call for later, with an open invitation to visit anytime.
Never answer the door and let them leave. Or open the door, threaten them with a clear message they're not welcome to return.
The dog is barking. Must be someone at the door.