That's the advice someone gave me when I told him I was having trouble with the novel I had started. I scoffed at him that that wouldn't make very good art, but he just nodded wisely, as if that didn't matter.
And, of course, it doesn't. Only I don't want to be happy, so I can't write that. But I can write what's on my mind and I finally started doing that. As much as I like reading fiction, creating it does not seem to give me any satisfaction, perhaps because I'm not good at it. Fortunately, I can always tell bad writing when I see it. I just can't always help it.