Despite trading lower for much of the day, the S&P 500 Index (SNPINDEX:^GSPC) managed to stage a comeback, and end in the green on Friday. While the market found out that consumer sentiment reached a six-year high in July, Wall Street is anticipating even more substantial news next week as the Federal Reserve meets up again to discuss monetary policy. The S&P added one point today, or 0.1%, to end at 1,691. 

By no means should the small gains in the index be taken to imply all-around bullishness. Shares of Expedia (NASDAQ:EXPE) should help to illustrate that point fairly well, as the S&P component cratered a massive 27.4% on disappointing earnings. Expedia would best be classified as a growth stock at current valuations, meaning investors have high expectations for the business moving forward, and believe it can increase profitability more rapidly than your average stock. That, however, was not the case on Friday, when the online travel company reported earnings per share that fell 28% from the same quarter last year. Yikes.

Data storage company SanDisk (NASDAQ:SNDK) also saw shares slip, though the 5.9% slump today doesn't quite compare to the precipitous drop in Expedia's stock. SanDisk already reported earnings for its most recent quarter; in fact, SanDisk grew at a blistering pace, with sales rising 43% in just a year. While that strength gave the stock a boost last week, this week, the stock corrected, falling 9% as investors reigned in their optimism. 

Lastly, Micron Technology (NASDAQ:MU) shed 5.3% on Friday. The semiconductor company may, like SanDisk, be a temporary victim of its own success. The stock is up 144% from 52-week lows, and less than 14% off the 52-week highs it reached in the last month. Part of today's decline is due to anticipation that NAND flash memory, used frequently in higher-cost smartphones, may slip in the third quarter after recent smartphone sales disappointed. As a producer of NAND flash memory, you can see why this wouldn't bode well for Micron.

Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.

The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.