There are different types of auctions. For example, with a reserve price (minimum price). Bidding starts at some pretty low prices, and upon receipt of bids, the price rises. If reserve price is not reached at the end of the auction, the goods are not sold.
Some sellers are confident in the liquidity of its product, and initially put low rates on their lots. Because according to statistics, these lots sold for the right price in 99% of cases.