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 Calix (NYSE:CALX) plunged more than 10% Thursday after the company announced disappointing preliminary fourth-quarter estimates.

So what: Fourth-quarter revenue is now expected to be in the range of $93.5 million to $94.5 million, which will translate to adjusted earnings per share of $0.02 to $0.04. That's well below the already-weak guidance provided by the company in October, which drove shares down more than 30% after it called for Q4 revenue between $97 million and $103 million, with non-GAAP earnings per share of $0.03 to $0.08.

Meanwhile, analysts were looking for adjusted earnings on the same basis of $0.06 per share with sales of $99.53 million.

Now what: To explain the revision, Calix stated it's seeing a "greater than anticipated decline in traditional year-end 'budget flush' customer spending patterns than the company historically has experienced."

As a result, and even with shares currently trading around 12.5 times next year's estimated earnings, I can't blame investors for taking a step back until Calix can prove this lull is short-lived.