It depends, I think experience in any way or form is going to play a large part into running your own company. If you don’t know what your doing, you are not going to have a successful one. There is only so much you can learn on the fly, and if you have employees you need to show them you know what your doing and the company is going to be a success or their moral may drop dramatically.
If you go to school for Business that may be the experience you need. If you’ve grown up around parents who are business owners, that may be your experience. Others need to go through the process of learning by working for others. The information you can retain on how companies work, how they make money, and what makes a success and what makes a failure can be important information when tackling the mountain yourself.
Personally, I feel the more broad your experiences are the more you can combine to help make your company thrive.