Unwinnable by Mistake/Tabletop Games/Choose Your Own Adventure


 * Some Gamebooks may require you to document usages of items, and if you accidentally forget you had an item...oops! Unwinnable!
 * Generically; if you got one from the library, you might have had a page ripped out so that you couldn't complete it.
 * In one Lone Wolf gamebook you are tasked with solving a demoness's riddle. It's been well over a decade and no one has ever solved it -- the answer can be found by flipping through pages to find the appropriate section (and thus getting the number) but that number doesn't seem to satisfy the riddle.
 * The 4th wall breaking solution this reviewer admires in Creature of Havoc is in fact just a proofreading error.
 * There was also the possibility of translation or paragraph number errors in foreign editions; among others, J.H. Brennan's The Curse of Frankenstein's french edition had, straight at the beginning, an inescapable paragraph loop.
 * In some of the Goosebumps books, they could be unwinnable by mistake. Specifically, the one about the cave spirit, which actually required you to document and keep track of items or spell talismans. It's possible to have forgotten you had one.