Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of electronic payment company VeriFone Systems (NYSE:PAY) plummeted 38% today after its first- and second-quarter outlook easily missed Wall Street expectations.

So what: VeriFone's preliminary first-quarter results -- EPS $0.47-$0.50 versus its prior view of $0.73 -- and downbeat second-quarter guidance are forcing analysts to drastically recalibrate their growth estimates. While management blamed the gloomy outlook largely on the economic weakness in Europe, investors are worried that such a wide miss suggests far more serious internal and competitive challenges.

Now what: Management now sees second-quarter EPS of $0.45-$0.50 on revenue of $435 million-$450 million, well below Wall Street's view of $0.80 and $517 million. "While we are disappointed with our performance and execution, we have a firm grasp on the challenges we faced and are taking aggressive steps to strengthen our competitiveness over the long-term," said CEO Douglas Bergeron. "We are confident in our ability and committed to executing against our strategic priorities to drive shareholder value." With the stock now off a whopping 65% from its 52-week high and trading at a forward P/E of 5, betting on that turnaround talk might even be worth looking into.

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