If you study billionaires you will see the link. Take for instance Sir Brandson. It is said he has over 250 individual companies. If you and I can do that then we will be able to duplicate Mr. Brandson's success and attain the level of success that he has attained.
Look at all the other billionaires and you will find that many that have done only one business, Dell, Gates, Buffet, but there are others who reach across industries like Mr. Brandson, and soon me and you. lol