While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a look at particularly stock-shaking analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of The Gap (NYSE:GPS) slipped 1% this morning after Goldman Sachs downgraded the teen apparel retailer from "buy" to "neutral."

So what: Along with the downgrade, analyst Lindsay Drucker Mann lowered the price target to $40 (from $42), representing about 9% worth of upside to Friday's close. While contrarian traders might be attracted to the stock's steady decline over the past three months, Drucker Mann believes that Gap's appreciation prospects remain limited given the near-term headwinds working against it.

Now what: Goldman expects Gap's comparable-store sales and gross margin to remain pressured for the rest of 2013.

"Recent data points have left us incrementally more concerned about the prospects for 3Q13 and holiday: (1) GPS September sales report exposed vulnerability to macro challenges, including traffic weakness and a need to step-up promotions; this is a change for GPS which YTD was insulated from macro weakness, (2) pricing points to a tough October for the Gap brand, and (3) we see little to improve the course of business between now and holiday," cautioned Goldman.

For value investors with some patience, however, all of those short-term concerns might be providing an attractively low entry point.