Why is it certain additions of certain books start off with different page numbers? I mean, some books start on page on, yet others start on page three, or even seven? What’s the deal with skipping pages? Is it really so important that people perceive your book to be 316 pages as opposed to the 312 it actually is?
Why do some books do this?
There could be a title page that precedes the first page of text. The title page is page 1, it’s followed by a blank left (also called a blind left) page (page 2), and then the first page of text is page 3. The convention is that odd pages are always rights (rectos) and the evens are always lefts (versos). It could also be that the publisher planned more front matter (counted in lower case roman numerals) than were actually used. If the imposition (ie, the arrangement of the pages in groups for presswork) is started before all this has been settled, extra pages can be added to cover the mistake. I’ve seen it, and I’ve done it in medical publishing. Hope this helps.
Some of it may also have to do with postal regulations. I know that with magazines everything is counted as a page, including front cover (inside and outside) and subscription cards. it may be that books are subject to similar regulation.