I've never just been able to out and out say about my books, "This is good."
Always the doubts, plus what do I know?
I usually say something like, "It's as good as I can make it."
But I put the work in on The Dead Spend No Gold: Bigfoot and the California Gold Rush. I kept working on it until I thought it was good. It was edited thoroughly twice, and I responded to every criticism. I didn't cop out with "it's good enough" and I wasn't intellectually lazy, as I have a tendency to be. I polished it until it clicked.
Lara gave it a final edit, and yes, I pay her, but this is what she had to say.
"I love the way it turned out! This iteration is more rounded, better developed and has lots more detail and description. It's definitely on a par with Led to the Slaughter now."
To which I say, I think so too.
What's happened is that I've made sure that I'm proud of each book before I release it. As inconvenient as that is, and as little as it probably matters on how they ultimately do, I plan to continue this policy.
I told myself to be patient when I started this, and I've stuck to that so far, and I think the quality of the writing shows it.
Most of my beta-readers see early drafts. The quality really seems to jump in the last draft, as if everything pulls together.
Good for me. Heh.