In the financial media, I see quite a lot of headlines to the tune of "Intel (NASDAQ:INTC) beats, shares drop." Indeed, there appears to be quite a lot of confusion around just why the company's shares dropped even after what, on the surface, looked to be "good" earnings results.

There have been a number of explanations for why Intel shares dropped, running the gamut from plausible-sounding ones such as "the data center business slowed down" all the way to the ridiculous ones like "this megacap stock is begin manipulated by evil short sellers."

However, I don't buy any of them. Here's why I believe Intel shares declined post-earnings.

Intel lowered guidance
During its November investor meeting, Intel said that it expected 2015 revenues of around $55.2 billion in revenue. For 2016, it guided to revenue growth of between 5% and 7% from 2015 levels, implying a revenue range of about $57.96 billion to $59.06 billion, with the midpoint at $58.51 billion.

In the company's fourth-quarter earnings release, however, Intel lowered its full-year guidance.

This wasn't immediately obvious to many investors because Intel didn't explicitly give guidance for its "base" business excluding Altera; it just gave full-year guidance with Altera baked in.

On the call, management indicated that it expects its newly acquired Altera business (which Intel will call its Programmable Solutions Group) will bring in around $1.6 billion in revenue during 2016.

Computing the dollar range implied by Intel's new full-year guidance, which calls for revenue to be up anywhere from mid to high single digits (off a base of $55.4 billion, since the company slightly beat expectations), it looks as though Intel is guiding to $58.17 billion to $60.39 billion in sales. Minus the $1.6 billion contribution from Altera, we get an organic revenue range of $56.17 billion to $58.79 billion, with the midpoint sitting at $57.48 billion.

The new guidance is effectively a full $1 billion reduction from prior on an apples-to-apples basis at the midpoint.

Uncertainty looms
Although it's good that Intel got the guidance reduction out of the way now rather than maintaining guidance and then warning before the first-quarter results were out, I believe another thing that could be bugging investors (it's bugging me) is that the outlook cut came so early in the year.

Remember that Intel brought down its full-year guidance not once but twice in 2015 (it went from growth to flat, then flat to a slight decline) and missed its growth targets in both of its major business units (Client Computing and Data Center) for the year.

I think that investors may be worried that further guidance cuts may be coming. After all, if the macroeconomic situation, particularly in China) degrades further, a fear that appears to be quite prominent in investors' minds -- then this could lead to further downside in the company's main business units.

Is the stock attractive following this plunge?
Intel stock is quite cheap here, trading at just over 12 times analyst consensus for the current year. Furthermore, over the long term, I think that Intel's business should be in reasonable shape, with its non-PC businesses continuing to grow, making it easier with each passing year for those businesses to offset any other declines in the PC business.

This isn't a stock that's going to make anybody rich overnight, but I do think it's a stock that investors looking for reasonable capital appreciation and a nice dividend over the long haul should at least take a look at. 

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.