Making art of any kind is risky. It isn't just something you've made and put up for auction. No, it's part of yourself. Though a person's work may not be autobiographical, or revealing in the gossipy sense of the word, it exposes everything that artist is. It shows you our thoughts, our beliefs, our skill -or lack thereof. It can tell you our place in society, and whether we care about it.
For visual artists, it is terrifying to pour yourself into a piece that your average viewer will spend three seconds on. Yes people, count them, three. Three seconds for your entire being to be absorbed, chewed up, and spit out like a bite of stale bread. I wish this was an exaggeration, but it is not. If your work does not get someone's attention in this time, it is staying home with you, forever.
For a writer, and I am only speculating, the fear is whether people will even pick the book up. It seems like very few people read for pleasure anymore, or are unable to finish any book they begin. And even if they do purchase, read, and enjoy what you have to say, will your readers understand it? These are daunting concerns, and we have no choice but to pretend they don't bother us, and press on.
So we must remember this:
Artists who seek perfection in everything are those who cannot attain it in anything
Let go, and dive in!