Timing may not be everything, but it counts for a lot, especially in promoting books.
I learned this the hard way with my first two collections of poetry. The first, The Hypothetical Landscape, was published as part of the Quarterly Review of Literature Poetry Series in 1999 and is presently out of print. (I may see what I can do to change that.) At the time the book came out, though, I was working two part-time jobs with no benefits and was in no position to attempt a book tour or any other major promotional efforts. Nor did it help that I wasn't hooked into the academic networks that lead to of readings and events.
I did not make the same mistakes when my second collection, Settling for Beauty, was published in 2005. I can't even say that I made new and different mistakes. But I did learn one valuable lesson: if you are publishing a book and planning a wedding from a distance, and doing all that while working full-time, something has to give.
For me, like the vast majority of people, not working was not an option. Even less of an option was changing wedding plans. So fully promoting Settling for Beauty gave way at the time, and I have no regrets about that, per Edith Piaf, especially now that I am about to celebrate my fifth anniversary with the wonderful Paula Van Lare.
There won't be quite as much on my plate when it's time to promote my forthcoming book of essays; there will be more to come on that. Things should also be similarly tranquil when my third and fourth collections of poetry come out. In a moment of guarded optimism I say "when" rather than "if" because one of the two manuscripts, a collection of formal verse, has been a finalist in two contests.
But for now I hope to give at least a little attention to Settling for Beauty. If you follow the link you can see a few sample poems. Another poem in the collection appeared on Verse Daily.
Virtually any writer is going to look back on older work and think of how it could be better. I am no exception. Still, new poems (and essays and fiction, among other things) need to be written, and time is short.
In any event, I am still very fond of that book, and I think the linked samples will give you an idea of why you might become fond of it as well. You are welcome to let me know what you think.
The title of that book, in case you don't feel like scrolling up, is Settling for Beauty.