Titanium: Among other things. When you beat a hard game (but not instant kill hard, that's cheap), you feel like you earned your victory. Nowadays it's not all that impressive to beat a game, because the're all more or less failure proof. It goes with the all important instant gratification in new and casual players, who bog the market now.
I'm not particularly bothered that games aren't Nintendo Hard anymore. When I was a kid, my head was hard enough to beat against a wall for hours, especially since I only had a few games to play, but nowadays, I'd rather just go play something that won't waste my time.
I like challenging games. Games aren't much fun if they're too easy, but practicing the same stretch of ground thirty times because the developers thought they were making a coin-op is monotonous and frustrating. There's a point when the drive to succeed gives way to the desire to just get it over with. There's no satisfaction in that.
I don't have much patience for reading heavy manuals anymore, either. If it's a complex game, then sure, give me a book with all the details I need - but teach me the basics in-game. Give me tooltips and tutorials, and let me learn how to play by actually playing - I'll learn better that way, besides. If the game is interesting enough that I want to learn more, I'll pick up the manual on my own. A game can be accessible and complex at the same time.