It's frankly ridiculous how close some games are to finished when they are cancelled -- or, conversely, how vaporous they can be when they're first shown. At trade shows, you see maybe 50 games in the space of 4 or 5 days, and a small proportion of them fade into the background and are never heard from again. Sometimes you see something at Gamescom or E3, forget about it for years, and then suddenly think "Hey, whatever happened to that?"