Firstly, eBook Factory produces virtually any eBook format. This is because it extracts all graphic and textual material from InDesign in all its richness, and brings them to its database. That is, does not directly produce "XHTML for Digital Editions," but produces content in a "template format" that can be transformed to any other.
As an example, the Mobipocket format can occur while the epub or another. You can even generate different types of epub targeting different eReaders, if desired. Therefore, you can forget what will be the winner format or their evolutions. Having the XML and JPG of your books in a database, you are able to export again anytime. Definitely a nightmare less for the editor.
Thirdly. The cost. Yes, the cost again. Because not only is matter of cost reduction and to good roles sharing. To obtain an epub from InDesign, for example, you have to do some extra work: local formats, tables of contents, fonts... For new books is possible afford that extra cost. But does that mean that you need to spend hours of previous work for each of your books, before you can make an eBook? No, if you use eBook Factory. This is due to several reasons. A couple of examples: eBook Factory extracts "rich" XML from InDesign. All formatting and typographic control is incorporated into the XML, so the system can produce very well formatted eBooks without having to do extra work in InDesign. And the images. We do not mean normal images that can appear in a document. InDesign export images very well. We mean those box based assemblies, lines and strokes that are not really an image. Or tables that can never be the same in InDesign and XHTML. eBook Factory export JPG automatically from those assemblies. These are just some of the advantages of eBF industrial system.