Timing is everything

Whenever I go to Amazon, I check for various DVD titles I want to make sure to order once they're announced. I'd been keeping an eye out for a whole-series collection of Stargate: SG-1 because I came to the series late and have enjoyed what I have seen of it. So a few days ago I noticed that a full-series collection had shown up, with a pre-order sale price around $215 (and a list price near $300). Today, the pre-order price is about $275. Quite a jump!