Recently Amazon and other e-book retailers made it possible for independent publishers (like me) to take pre-orders for a new book, just as they do for traditional publishers. The hope is that there will be enough pre-orders to kick-start the book's climb through the rankings. How does that work? Retailers accept the orders but do not charge them or record them as purchases until all those pre-orders are entered in one batch on launch day.
I tried this for my first historical novel, Damned Yankee, which launched on May 1, 2014. Again I was not impressed with the outcome. Yes, a few of my faithful readers dutifully pre-ordered their copies because I asked them to do so. I had the book on pre-order for a solid month, and there were only seven pre-orders on Kindle, and none on Apple or Nook as far as I can tell.
My readers really didn't like doing pre-orders, and several told me so. Truth be told, there was not a single advantage to be gained by making a purchase early. Unlike a product whose supply might run out before you could get to the store, e-books never run out. So the pre-orders did not cause any sort of wild mob of lined-up buyers at the time. On the morning the set went live on Kindle, the seven pre-orders all came in at once, and they had absolutely no impact on the book's ranking. A couple of months later, the book took off well on its own and sold hundreds of copies a month for the rest of the year. The pre-order option turned out to be another waste of my time. Would I bother doing it again? Probably not.