Amazon claims that so far the program has been a success. In December of last year 295,000 books were borrowed paying each author $1.70 per borrow and the KDP Select lending library has swelled to 75,000 books. As a result of this, authors and publishers participating in the program increased their income by 26%. The company now has increased this fund from $500,000 in December to $700,000 in January.
In addition to the money earned from books being lent, Amazon also noted that sales of KDP Select tittles also increased compared to those that were not in the program. An evaluation of Kindle owners participating the in the program compared to those that did not revealed that the ones participating bought 30% more books than the ones that didn't.
The combined effect of royalties coming from borrowed books and from sales of more books has resulted in the top ten KDP select authors growing their book income 449% from November to December.
By permitting authors to give away their book for free for a few days, Amazon has given them a powerful promotional tool that allows new readers to discover them. Overall the KDP Select program has had the effect of allowing self-published authors access to the top 10 slots of the different genres, displacing books by more traditional publishers.
So it's that easy eh? Enroll your book in the KDP Select program, give it away for free for a few days and sit back and watch your sales increase.
Not so fast.
Giving your book away for free only seems to drive its sales after the free period if your book makes it to the top 100 in the charts of its respective category. Therefore making your book free is not enough. You have to promote your book to make sure it gets enough downloads to reach that magic 100 bracket. Thus authors have to alert their e-mail contacts and work their social media to let readers know their book is free on a particular day. In fact, some authors have placed paid advertisements in major book blogs. Yes, you read that right. Pay money to let readers know that you are giving your book away for free!
The program seems to work best for authors with several published books because free promotion of one of the books will drive sales of the others. This is especially true if the book being promoted is part of a series. Also, having more books in the program gives you more free promotional days. Finally, the genre in which the book is in also seems to matter. If your book is in the more popular genres, it will tend to get more downloads when promoted.
So the answer is yes, the KDP Select program seems to have worked for self-published authors as a whole but in general it favors those who have been around longer, have more books, and/or are able to marshal the promotional forces that can make their books reach the top ranks. For the no-name author who has put out his/her first book it is an additional promotional tool but the climb to the top is still steep.
There are two final considerations to be made. One is that, as the KDP Select program becomes more popular, the market will be swamped with free books and its effectiveness may decrease. The other consideration is that the avalanche of free books may provide a windfall for book plagiarists who can now obtain many books for free and quickly republish them with new covers and author names. This is a big problem at Amazon and it's getting worse every day.