Ownership implies at least three things:
Anyone can register a company and immediately satisfy all three criteria. However, the day-to-day practical reality of business ownership is rarely that straightforward.
Many entrepreneurs are trapped in a business that wouldn't survive for long without their constant involvement. They work far longer hours than they would if they were employed somewhere else, and the constant demands on their attention frequently bleed into their personal lives.
Most owners are so busy working in their business that they rarely get around to working on it. They personally go to great lengths to look after their customers, employees, and suppliers, but struggle to build the organisational capacity that their business needs to operate independently.
Finally, almost all entrepreneurs make extraordinary sacrifices for their business, but very few are compensated for their risk. Some are able to pay themselves a generous salary by virtue of being the boss, but their actual ownership earnings (e.g. dividends) are frequently nil.
The ultimate challenge for every entrepreneur is transforming their business from a place to work into an asset that can create ownership wealth independent of their involvement. Until then, it's debatable whether they own their business, or whether their business owns them.