a unicorn like you're mentioning isn't linear. a 1% 1000x business probably can stop along the way when you reach a TC you're comfortable with, that you have a 1% of hitting that 1000x doesn't mean you don't have a 25% of hitting 2-4x with the same idea before. There's a lot of people who made their money by bootstraping business 0 to 100k, etc, and selling. (There's also people who center on buying 100k business and growing it to the million stage... and so on)
That sounds like being an actual founder though in which case downside is large. 0 (or negative) TC because you have no profit and you are bootstrapped.