She painted what she painted because she had to, because she was passionate about it. She didn't care at all if people bought her paintings. As she said, she painted her reality.
I find that I make as an artist the kind of choices that I have to be impassioned about. I'm not going to spend two years on a film or four years on an opera if I don't feel like I can put my own self into it. That doesn't mean it has to be about myself. That's a difference.
Frida painted her own reality, her life. I'm a director and I paint many other people... Other people's realities. But I do have to invest in it.

On Frida Kahlo's work and her own - Bill Moyers interview (2002)