The problem there is, longevity. How can they separate the good from the bad and the downright awful?, as you rightly say, games often end up at that price after their term. But if they were to ship at that price the only way they could mark off would be to give them away, and that's not a viable option for anyone. I think as the prices on PC games stand, it is a healthy balance between relying on volume and the profit of each unit shifted, unfortunately moving either side of that balance means taking a gamble. A game priced at £30 on launch, say for instance that game isn't very good, recent examples like TDU2, AVP and I predict Homefront. They (apart from the latter) have dramatically fallen in price, just like you said into the £5- £15/20 price range. Now those developers can rely on people seeing this and buying into it under the belief they are getting a bargain, which is going to generate that volume of sales, the big money was probably made shortly after shipping at the full price tag, now they can fill in those gaps.