In The Hobbit Bilbo finds himself in a deadly serious riddle game with Gollum, which he wins by accidentally asking "What do I have in my pocket?", a question that Gollum can't answer. Even Bilbo privately admits that this wasn't a proper riddle, but consoles himself with the rules-lawyering interpretation that by accepting the question as a riddle, Gollum has only himself to blame.
Today Final Fantasy XIV comes out, and it will pose many improper riddles like "What do I have in my pocket?" to thousands of players. FFXIV is built on the principle of not telling the players anything, they have to find out everything for themselves, even if that often requires stumbling upon the answer by accident, or systematically trying all possible solutions. Only, of course, players won't do that. As everybody has the same problems finding out how everything works, and some people already did find out many things in the beta or Collector's Edition pre-play period, the answer to all these "riddles" can be found on the internet. Why would anyone for example try crafting by trial and error (or by writing down recipe information received as "reward" from crafting quests with pen & paper, as the game doesn't log them), when he can find the recipes in a database?
The irony is that if given a riddle that looks doable, many players would try to solve it by themselves, because that is part of the fun of the game. But FFXIV being deliberately hard and obscure, to the point of leaving players completely in the dark, most players will either give up completely and unsubscribe, or play the game with a browser in the second window. I seriously doubt that many people will play this game "as intended" through trial and error.
It is debatable whether letting players find out everything for themselves is good or bad game design. What isn't in doubt is that it simply doesn't work as long as your challenges to find out stuff are fixed. Among thousands of players some will usually arrive at the solution (well, FFXI had a mob nobody ever found out how to kill before it was nerfed), and then post it somewhere for other players to find.
The Hobbit, and therefore the Lord of the Ring which follows, would have been a very different story if Gollum would have used his smart phone to Google the answer to "what do I have in my pocket?". If devs want to puzzle their players, they need to invent riddles that have a different answer for every player.