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

What: Shares of Michael Kors (CPRI 0.08%) slipped about 2% on Tuesday after Barclays initiated coverage on the specialty retailer with an underweight rating.

So what: Along with the bearish view, analyst Joan Payson planted a price target of $85 on the stock, representing about 14% worth of downside to yesterday's close. So while momentum traders might be attracted to the stock's strength over the past year, Payson's call suggests investors could be underestimating some of the challenges that could weigh on Michael Kors' growth rate.

Now what: According to Barclays, Michael Kors' risk/reward trade-off isn't too appealing at this point. "[W]e expect that strong growth in Europe could be offset by the North American business, which we think has reached a point of maturity more quickly than anticipated and may begin to decelerate," said Payson. "Assuming a slowdown occurs, we expect margin pressures will become more evident, tempering EPS growth." Of course, with Michael Kors still sporting a reasonable PEG of 1.2 and boasting a rock-solid balance sheet, long-term-oriented growth investors might want to take that bearishness with a grain of salt.