Some clever spinmeister seems to have orchestrated a coup for Facebook last week: The company’s stock hit a six month low, but the headlines were all positive. The morning after the nadir, you see, two investment banks upgraded Facebook shares, nudging the stock ever-so-slightly upward.

The news cycle had been successfully hijacked away from the actual market and handed to a couple of the banks that purport to predict its gyrations. “Facebook Gets a Pair of Upgrades; Shares Rise,” reported The Wall Street Journal. “Facebook shares jump,” said Reuters. The upgrades traced back to reports, including one in the Financial Times, that Facebook will roll out video ads in July. Facebook bulls are betting these video ads will quickly turn into multi billion dollar businesses, just as Facebook’s mobile ad businesses exploded into a $1.9 billion revenue line over the course of just one year.

In the two trading days after the video-ad upgrades, Facebook stock rose 4 percent, ending the week just above $24 per share — a very modest gain over Wednesday’s six-month low of $23 and still well below the $32 the stock reached in late January.

The real question isn’t why Facebook got upgraded, it’s why Wall Street has returned to such a bearish position on the social network. Barely one month ago Facebook turned in better than expected earnings driven by robust growth in mobile. Again, shares briefly nudged upward (by 6 percent) before gliding steadily downward over several weeks. After beating Wall Street expectations even more widely in January, the stock actually declined, beginning a long fall from which it has never fully recovered.

Trying to extract a coherent rationale from the aggregated result of tens of millions of individual stock trades is, in the absence of a massive and truly obvious catalyst, pointless. In other words, one can only guess at the (potentially endless) reasons Facebook is in the Wall Street doghouse again, and people are of course doing just that. Here are some of our pet theories, mostly centered around the idea that Facebook is taking on more risk, launching new products in new markets and pushing the comfort zones of users and advertisers alike :

Facebook’s bulk up is risky. Costs are rising 50 percent in 2013 as Facebook goes on a hiring binge. The company has stated revenue will not rise accordingly.

Costs are rising 50 percent in 2013 as Facebook goes on a hiring binge. The company has stated revenue will not rise accordingly. Facebook’s new products are far from making money : Launches like Facebook’s Open Graph search engine and Home mobile apperating system generate headlines and suck up resources but will need many quarters of refinement before Facebook even begins to try generating revenue from them. On the last two quarterly earnings calls, CEO Mark Zuckerberg has explicitly warned Wall Street not to expect money from these products anytime soon.

: Launches like Facebook’s Open Graph search engine and Home mobile apperating system generate headlines and suck up resources but will need many quarters of refinement before Facebook even begins to try generating revenue from them. On the last two quarterly earnings calls, CEO Mark Zuckerberg has explicitly warned Wall Street not to expect money from these products anytime soon. Facebook ads are increasingly generic: Investors were initially optimistic that Facebook could disrupt the online advertising industry by offering truly social ads, ads that could only happen on Facebook, like those “sponsored stories” where your friend likes some brand and the brand pays to keep the Like showing up in your News Feed for weeks on end. But Facebook’s recent ad products have been all about turning the social network into a really good platform for essentially conventional ads. Facebook has learned to combine its extensive user demographics with information on where else you’ve been on the web, what you buy at the grocery store, what apps you have installed, and where you are physically located. It has successfully pushed its ultra-targeted ads onto smartphones and (reportedly) into videos, driving Facebook's recent revenue growth. But anyone else with basic demographics and the willingness to rent or acquire similar databases could assemble comparable targeting capabilities; Facebook is not leveraging its fabled social graph in many of these ad products.

No one can honestly claim they know why Wall Street hates Facebook right now. But it's clear the social network will have to learn to ignore stock gyrations (and laundry lists of complaints like the one above) if it wants to preserve its long term strategy. Time and again Facebook has defied the suggestions of seasoned technologists and financial sages alike, and time and again it has paid off. Facebook, presumably, feels right at home in the doghouse. (Welcome back.)