If we are accustomed to business, it can be said that the theory in building a business is almost useless, with deep experience, we can more easily manage the business, unfortunately many people are afraid to start the business for fear of losing or bankrupt.
It's a good thing to have that fear because if you don't, you will waste a lot of money by trying a bunch of different businesses without putting proper effort and working hard on a single venture, when you have yourself involved in almost everything, you will most likely get success in none of them, the best way is to start a single business and keep working on that, if you know you have enough resources and can work hard on your business, it will become successful eventually.
People who have no fear of losing or going bankrupt tend to waste a lot of money which they shouldn't, you can always see, only the businessmen who have their hands in a single industry are successful in that particular business, but those who try having more and more businesses tend to get less success in comparison to them.