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What: Shares of transportation and logistics company Werner Enterprises (Nasdaq: WERN) fell as much as 11% earlier in the trading session, following its preliminary third-quarter earnings guidance.

So what: Werner is now forecasting that its third-quarter EPS will be in the range of $0.33-$0.36, versus Wall Street’s projection of $0.44. Werner is blaming the rising cost of salaries, fuel, health-care benefits, maintenance, and depreciation of trucks as the reason for the weak expectations. BB&T Capital also downgraded the company to "hold" from "buy" following its guidance.

Now what: About the only thing we were missing in that list of excuses was the kitchen sink! Swift Transportation (NYSE: SWFT) is dealing with similar fuel costs, but it managed to top expectations in the second quarter. Similarly, even Arkansas Best (Nasdaq: ABFS), which is now firmly on my radar, beat expectations, due to increases in its pricing. If some of the weaker transportation companies are succeeding, why isn’t Werner? That's not exactly an answer I have right now, but it’s definitely a reason to be leery of Werner at the moment.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.