I don't think personal wealth of an owner has anything to do with a business. I'm probably a greedy SOB, but that's his money, not the company's money.

If the company can't exist without him paying his own money into it, then the company probably shouldn't exist.

I find it laudable if an owner would help float a company through a short bad period using their own money, but I wouldn't expect them to beggar themselves (or not get paid back) just to keep a failing company running.