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What: Shares of Groupon, Inc. (NASDAQ:GRPN) were going for a discount again today, falling as much as 20% after the daily-deals merchant posted weak guidance in its first-quarter earnings report last night.

So what: This is far from the first time Groupon has disappointed the market with its guidance, and yesterday's report leaves investors again questioning if the company will ever become consistently profitable. Results in the past quarter were actually better than expected, as the company's adjusted loss-per-share of a penny beat the analyst estimate of a $0.03 loss, and revenue grew 26% to $757.6 million, topping the consensus at $740.1 million. Still, for the current quarter, the company projected earnings of just breakeven to $0.02 a share, below estimates of $0.03.

Now what: Though Groupon's revenue soared 26% in the quarter, much of that is due to its transition to a goods-based model rather than a daily-deals one. Gross profit in the quarter improved just 2%, indicating that almost none of those additional sales are hitting the bottom line. Downside guidance may be getting the blame for today's drop, but Groupon's inability to prove the validity of its business model seems to be the greater culprit for the stock's weakness more than two years after its IPO. Notably, the company raised its full-year EBITDA guidance slightly to $300 million, as it said the current quarter's lower guidance was based on "continued investment to accelerate long-term growth." Given that long-term focus and improved full-year outlook, I'd say today's slide seems exaggerated.

Jeremy Bowman has no position in any stocks mentioned, and neither does The Motley Fool. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.