A business owner? If you've found success, you own a lot of businesses. If you haven't, you own one even though you have started more than you currently have. You're still just a business owner.
So, in my example above, what if the person only retains a minority ownership stake in the restaurant, sold the two software companies, the property management company failed, and they are now working on a new company of any kind? Does "business owner" really accurately describe what they do?
Note that if you think this kind of example is unusual, in my experience it's relatively common for people who build companies to do so in different domains, either simultaneously or at different stages in their careers.