As one in charge of printing a county family history book, I can state: 1 Because of the expense, books could not be printed without pre orders. When the cost gets into the many-thousand dollar range, loans are too risky and expensive. 2. Because of most work being done by volunteers, (usually one person or two) Any shift in their schedule (death of family, new job, etc.) throws off the schedule. 3. Pre-orders generally get the book at lower cost than others, sometimes a fairly significant saving. TN