You are joking.... Right?
Seems to make sense. In a market that is falling, if someone buys at current market, then as prices continue to fall, they will be underwater. Not to mention the fact that before a buyer can turn a profit, they need to get enough appreciation to cover the closing costs from the purchase plus the commissions that would be paid out on any sale. Anyone that buys in a falling market is likely to be underwater immediately unless they somehow bought below market (which by definition is very difficult to do as market means the price paid between a willing buyer and a willing seller).