This is why you will find all over the internet people telling you need to take Business 101 in order to find your path to monetary success, instead of only focus on your photography skills. By believing on it I have joined in a Business curse too, which I didn't enjoyed much because I couldn't identify the business mentality and view to my own.
We have to be careful about common sense, specially those repeated over and over again. Often people just repeat things without knowing what they are talking about as Derek Ridgers suggest.
Reading from Derek Ridgers what I founded out by my own experience, artistic brain and business brain are rarely found in the same person. When they are that person will almost always become a success. But even a person with both brains, for arts and business, can still fail when they don't have the psychological make up to sustain their success, he says.
His recommendation as best approach for highly talented photographers is to find someone else to do the Business 101 for them, meaning an good agent. That is not easy of course, since you need to have in some level of initial business success in order to attract agents attention.
This is the reason I think some people, without brain for business are better off without the stress of trying earn money from their talent. I have the opinion that many of them would hate to do most type of photography as business. The same way I hated, because I had to create what the client expected and not exactly what I wanted to do. You are not always free to experiment, explore, bring something new but sell what is already sold, meaning what you have shown previously. And not everybody is happy doing it, unless if you have some brain for business.
Even worst. The stress of obtaining monetary success, in a brain that not works well for business, can become a distraction from creativity and artistic talent. Which may be the reason why many artists and photographers are happy as starving artists or doing what they do as hobby. (And not because they are lazy vagabonds as some people like to say).