A few days ago, GameDaily ran a short story from EEDAR (Electronic Entertainment Design And Research.)
In this piece, the gist was that one in five games becomes a “success”, and that games which do not have playable demos before release sell better than games that do.
Although they may have come to this conclusion by a statistical, scientific means, I think anybody with more than three brain cells can figure out anecdotally that what's going on here is that crappy games don't sell when people get a hands-on chance to see how crappy they actually are.
Even the worst piece of software can look like a superstar when the developers snip and edit selected pieces of footage to highlight non-playable cutscenes or clips from dramatic angles that couldn't possibly represent actual gameplay. I can think of dozens of games offhand that got me pumped after seeing a slick trailer, only to find that the final product was nothing near the grandeur of what was represented.
Granted, there have been several instances where the demo itself has not given a complete picture of what the final game really is—for example, games that employ complex mechanics that are introduced to the player over time through a series of tutorials usually seem like jumbled messes when someone checks them out at a kiosk for two minutes. The same goes for RPGs or games that incorporate lots of mood and atmosphere. These sorts of titles just can't be done justice without first laying the fundamentals down for the player. Honestly though, I think most gamers get this and don't count it against a game when the demo fails to capture the substance.
I may not be a researcher, but I believe that the essence of these findings is not the value of a demo, but rather, a statement on the quality of software being shoveled onto shelves with the take away message being:
“If your game sucks, make a great trailer and don't put out a demo to guarantee higher sales... because gamers will get suckered by the hype and waste their money on it.”
Great research there, guys… I don't think anyone is surprised.