There are two options on quibids with what will happen if you commit to an auction. Let's take a 10$ giftcard for example.
Road A: You don't win the Auction, but you've bid on in with 10$ worth of bids, so you end up buying the gift card for 10$
Road B: You win the Auction, and get it for an amount less than 10$.
To simplify it, shopping on Quibids is like walking into walmart with intentions of buying say, a 10$ item. You show up the cashier, and he flips a coin. If heads, you pay 10$ for the item like normal. If tails, you get an X dollar discount. However, if you know what you're doing, the odds of getting that discount is far higher than 50%.
In the end, you aren't paying more than 10$ on a 10$ item, with a good chance of having a discount.