Print-on-demand technology, POD, allows for single copies of books to be printed, one at a time, when a copy of the book is ordered. Traditional off-set press runs require a minimum number of copies to be printed at a single time. POD printed books can be printed in any combination of number of pages while off-set printed books must be printed in multiples of 16 pages for 8-up printing.
Both methods of printing have their advantages and disadvantages. POD costs more per copy once the number of copies, on average, reaches around 750-800 copies than an off-set press run, but the cost per copy using POD printing is less per copy than that of an off-set print run up to that point. For press runs of over 800 copies, the cost per copy is less using traditional off-set printing.
The advantage of POD printing for the self-publisher is that no inventory is kept on hand, no capital is tied-up in inventory and very little money is required up front to establish printing for the book. The disadvantage is once the book sells enough copies, the cost per copy becomes a factor with the off-set press cost being lower, allowing a greater copy per copy.
While POD technology is constantly improving, there is some drop-off in the quality of printing compared to that of off-set press printing. Another problem common to POD printing is that pages will at times be upside down or printed out-of-order. I personally have had this happen to several copies of books that were printed by CreateSpace, owned by Amazon.com. CreateSpace will replace the misprinted copies if notified within 30 days of delivery of the books.
If the self-publishing author knows in advance that the book is going to sell several thousand copies, perhaps because of an advance agreement to sell the book to a company as a premium item, a large book club order, etc, the economics of off-set printing make sense to print the estimated number of needed books. A technical book that might require exacting printing of graphs, charts, diagrams or other similar items might also need to be printed using an off-set press. Books that are going to be sold in small quantities over a period of time make more sense economically when printed using POD printing.
There are other cost factors that the self-publishing author should consider when choosing a printing method. If the book is only going to be sold via the internet using sales points like Amazon or Barnes and Noble, other factors enter the equation. POD printed books are printed only when ordered. Most POD books are printed by Lightning Source Inc. which is owned by the book distributor Ingram, which fills orders for both Amazon and Barnes and Noble. By using Lightning Source, self-publishing authors do not need to warehouse books. Ingram handles all distribution for the author, fulfilling book orders as only as the book is ordered.
Traditionally printed books not only have to be warehoused, but require heavy discounting, often in the range of 50-60% if not higher. POD printed books allow the self-publishing author to by-pass the middlemen and keep more of the profit. Since POD books sold via Amazon and Barnes and Noble are printed and then shipped, the self-publishing author can set a discount as low as 20% per copy. Experts in the field of self-publishing suggest a discount of 20% will not be listed/ranked high during searches by customers due to the software used by Amazon. Discounts of 40% seem to be the most effective discount.
The costs of distribution, and the discounts involved, as well as the costs of warehousing and shipping must be factored in to the cost comparison when deciding on using POD or off-set press printing. Like anything else in the self-publishing industry, there are trade-offs with both methods of printing. Do your homework and compare costs.