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What: Shares of titanium dioxide maker Tronox (NYSE:TROX) fell as much as 25% today, after the company released earnings.

So what: In the third quarter, revenue rose 5%, to $487.3 million, and income from continuing operations was $25.6 million, or $0.21 per share. But analysts had expected revenue of $532.1 million and earnings of $0.45 per share, so these results were a huge disappointment to investors.

Now what: An earnings miss is never good, but this was a huge miss on both the top and bottom line. Management said that it was still purchasing feedstock from prior contracts, and cost of goods sold will fall when the company is operating on a more vertically integrated basis. To make matters worse, the company bought back 12.6 million shares at an average price of $25.85, about $10 above today's price.

Earnings have swung wildly in recent quarters and, while I have hope for the company's value in the future, I simply can't be a buyer after such a disappointing profit.

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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.