The average book signing event usually results in about 6 books being sold. I say the "average" signing, because there are far too many authors that just expect the crowds will somehow materialize, or that the bookstores will run full-page ads in their city newspaper to promote their book signing events.
However, the reality is the bookstores expect the authors to bring those crowds to their businesses. They don't agree to host book signing events to promote the newest local author. They hold book signing events to attract new customers and make money, and they expect the authors to bring in those customers.
Recently, one of my authors sent me a checklist that she was given by a bookstore. The bookstore manager expected the author to do certain things leading up to the event to help ensure it would be a success. I won't mention which bookstore it was, other than to say it is one of the major bookstore chains. These were the store's expectations:
* The author needs to start promoting the event at least six weeks in advance.
* The author and their book should present timely topics of interest to the store's customers.
* The author must have the ability to attract 25 or more customers.
* The author must contact and work with the local media for coverage and promotion.
* The author should post their event dates on websites and social networking sites.
* The author should send out mailings, email blasts, and other communication to friends, family, businesses, community groups, etc.
* Last (but not least), the store's checklist mentions that having an event at the store "does not guarantee we will permanently carry your product in the store."
As you can see, the store has quite a few expectations of the author. What does the store promise to provide? In this case, the store told the author they would:
* List the event on their web site.
* Display a sign announcing the event in their store.
* List the event in the store's newsletter (maybe, but not guaranteed).
And that was it. Again, this was one of the major chain bookstores, which sells a lot of books and hosts a lot of author events. They are basically providing a venue for the author's event. Getting customers in the door...well, a lot of that is left up to the author. An author may get some assistance from their publisher, but not all publishers do so. Most expect their authors to be promotion machines.
With plenty of planning and preparation, book signing events can be great sales and promotional opportunities, and they give an author a chance to meet face-to-face with their readers (and potential readers).