Days like yesterday -- when the S&P 500 Index (SNPINDEX:^GSPC) surged to an all-time closing record -- can be extra tough for investors in stocks that end the day with huge losses. Shareholders in today's beleaguered few can at least take solace in the fact that the entire market was down, and down big. Falling more than 1%, the benchmark S&P index struggled to cope with disappointing jobs data coming just a week before earnings season kicks off again.

Of course, today's laggards fell much more than 1%. Oil refiner Phillips 66 (NYSE:PSX) cratered 6.6% just a day after posting 3.6% losses. The mean streak is due primarily to new regulatory proposals that reduce the sulfur content of gasoline. Though the Environmental Protection Agency says the new measures will add less than 1 cent to gas prices, refiners face some not-so-trivial costs, as they'll need to make fundamental changes to their equipment and processes. 

Sometimes you just can't win. Semiconductor producer LSI (NASDAQ: LSI) fell 4.6% Wednesday after an analyst reiterated a buy rating on the stock but had the audacity to indicate one area of potential weakness. The Maxim Group analyst, in the same note that gave the stock a price target with a 37% upside to today's close, remarked on how LSI was losing some hard-disk business to Marvell Technology. The jury's out until April 24, when quarterly results are due.

Lastly, Netflix (NASDAQ:NFLX) shares stumbled 3.9% today on news of a new, powerful entrant into the streaming-video market. Media giant Time Warner (NYSE:TWX) is launching its own monthly service to rival Netflix's, though consumers will pay $2 more per month. Time Warner owns a wide swath of quality content, which should help in the company's effort to chip away at Netflix's business. Potentially even more harmful to Netflix, though, is that it buys programming from Time Warner, and those prices may have just gone up.

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.