The biggest risk most people have when it come to building wealth is putting all their eggs in one basket.Having one full-time job supplying you with 100% of your income means you are either doing well or in a crisis.
Wealthy people and large corporations have multiple streams of income and continually work to develop more. Sometime the failures are huge. New Coke might be an example. In my practice I’ve had ideas cost serious money go down the toilet. I’ve also had spectacular successes.