There are many reasons 'why businesses fail'. You too may go in business and fail. Then why would you go in business if you can fail? There is no guarantees to anything in life. If business was so easy everyone would be doing it. Not all can be successful in business although I wish it could be. Some people by no fault of their own end up failing in business. They may have thought they had all the basics covered and that they thought of everything. That's why they choose a particular business, they thought it was a good business to go into. But unforeseen things happen that few if any thought possible. New inventions are created or there are changes in the economy that were unforeseen. Other "natural" events can literally wipe out a business like we seen happen on the Gulf coast because of the hurricane Katrina. In business one day, and the next due to a storm the business may not even exist. There are risks that we all take in life and with business you have even more risks can happen. Like your health may not allow you to continue the business and then the risks that you never counted on can spring up on you. One reason why people do not go in business is they can't afford or do not want to face the risks.
If you are a 'risk taker', which is part of the definition of an entrepreneur, your own business may be right for you. But make no complaints about it, there is risk and you may lose. How risky is it? You can buy insurance to cover some of the risks. Thinking ahead will be very important to stave off possible pit falls that may come your way. One of the reasons a business that takes little money to start or run is good (Businesses ideas on this web site) is that you alleviate one risk, that being losing much money on the business itself. If you want to go in the food service business like a restaurant, a small low cost way to enter that business may very well make more sense then trying to start with an expensive restaurant. Even if you have the money. Also, if you have the money it may be wise to hold on to some of it for unforeseen expenses.
If you are a risk taker and your own business is for you then you may be willing to take that chance to be successful and make good money with your own business. Be careful and think ahead and never think you 'know it all' because you don't and neither does the accomplished, rich, lucky, educated, or those that think they are wise beyond all others. Always keep an open mind to changes and how they will effect your business and how you can change with the times. Listen to you customers and even those you don't like or you think they aren't very bright. Even the most ignorant can tip you off on a good idea or problem that may effect your business. Best to your success and realize that even if you are successful, things can change fast. Always keep your eyes and ears open for new ideas and risks that can harm your business.