Your inner bargain-hunter may have heard the news that Sports Authority’s liquidation sales in hundreds of stores across the country begin today. That doesn’t mean that you should run out and gather up workout clothes and sports gear right away, though, unless you have a gift card to use up, since it will only be valid through June 26 June 28. That’s because of the strange way that liquidation sales work, where the prices on everything are hiked up before they’re brought back down.

Let’s say that you have your eye on a pair of sneakers with a list price of $120. Because of the weird games retailers play with pricing, the sneakers might have rarely been for sale for their full price: maybe they were marked 30% off before the sale began. A liquidation sale means that merchandise that was on sale before liquidators took over isn’t on sale anymore. The original price goes back up to 100%, and then the price gradually falls. The liquidator will first mark items down to 10% off, then 20%, finally escalating to some actual deals that might even beat sale prices at competitors.

Why do they do this? First, because the “going out of business” sale draws customers like swarms of locusts, and those shoppers don’t necessarily know what everything used to cost. Second, the liquidators handling the sale are a separate company that won the stores and their merchandise in a federal bankruptcy auction, and marking everything back to to the original price and then gradually lowering it is how they make money.

Another issue to keep in mind is that items are sold as-is. The companies running Sports Authority’s liquidation sales don’t mess around: they also ran Circuit City’s sales, and didn’t care even if they sold you a shattered television. You may have recoourse to the manufacturer with their warranty, but for very pricey items, check on that: make sure that items bought at a liquidation sale are covered under the original warranty.