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

Concerns about the sustainability of the global economic recovery helped push the stock market down from record levels today, as the wildcard of the government shutdown will likely keep investors on edge for months until economic data become available. Amid modest stock market losses of around half a percent, Cree (NASDAQ:CREE), Pacific Biosciences of California (NASDAQ:PACB), and Datalink (NASDAQ: DTLK) all fell much more dramatically today. Let's take a closer look to find out why these companies were market victims today.

Cree lost 17% of its share price today after the LED-lighting specialist disappointed investors with its earnings report. Even though a 24% rise in sales led to gains in net income of 89%, investors were hoping for a slightly faster pace of revenue growth from Cree. Even worse, Cree's guidance for the December quarter fell well below expectations. With the stock still trading at more than 80 times trailing earnings, Cree simply has no margin for error with high-growth investors who are counting on the strongest results possible.

Earnings were also the culprit for Pacific Biosciences of California, which dropped 19% after its third-quarter report. A drop in sales of its key DNA sequencing units hurt its results somewhat, although the company's loss was only marginally worse than investors had expected. The big question for Pacific Biosciences looking forward is whether it can turn its sophisticated genetic equipment into steady streams of cash flow, and until it does so, skeptical investors will likely keep scorning the company.

Datalink was the biggest decliner of the three, falling 24%. Earnings once again were to blame, as the company proved unable to convert rising revenue into greater profits. In particular, earnings-per-share figures that missed investors' projections by almost half led to a loss of confidence in the data-center infrastructure provider. With Big Data remaining a high-growth opportunity, Datalink isn't down for the count, but it will need to step up its game to compete with the rising number of players seeking their fortunate from data storage and analysis.

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.