These three companies just didn't live up to Mr. Market's expectations last week. Whether there was a target set by the company's own management, by Wall Street analysts, or by the market at large, that miss can have serious consequences.

Sometimes an earnings stumble is a signal to sell, but digging in the dirt is also a good way to find turnaround candidates while they're getting beaten down. Today, we have both short-term memory loss and long-term amnesia, and we'll see where this train takes us. And it's still National Poetry Month. Hence, the verse snippets where you might expect headlines. Enjoy!

Only remember me; you understand
It will be late to counsel then or pray.
-- "Remember," Christina Rosetti

Let's serve up some flash memory as an appetizer. Everybody expected a loss out of memory maker Spansion (NASDAQ:SPSN), but not one of this magnitude. The red ink flowed to the tune of $0.56 a share, nearly double what the consensus estimate had hoped for at a much smaller $0.24 per-share loss. Last year, Spansion lost $0.40 per share, so things got worse when they were supposed to get better.

According to research firm iSuppli, Spansion recently became the single largest memory supplier for mobile phones, edging out former No. 1 Intel (NASDAQ:INTC) with aggressive price cuts and deal-making with top-tier handset designers. Management claims things started to fall apart toward the end of the quarter and has plans for process improvement and more efficient memory designs that will help drive down future production costs. Included in these cost-cutting measures are consolidation of certain functional operations, elimination of outside services and some lower-margin product lines, and reducing their workforce.

This has an eerie ring of former parent company AMD. Seems like there's a family streak of chasing market share at nearly any price. Spansion share prices have never been lower than they are these days, so if you're buying the efficiency argument, this could be a good time to buy. Me, I'll wait for some proof of a true turnaround first.

Where art thou, Muse, that thou forget'st so long
To speak of that which gives thee all thy might?
-- "Sonnet 100," William Shakespeare

We're moving on to a more permanent memory specialist in data storage expert Imation (NYSE:IMN). You can forget the Wall Street target for this one, too, as $0.44 of EPS fell far short of the $0.61 average forecast. The stock price fell about 12% overnight, though it has since come back up a little bit as a jittery market tries to figure out the complex changes at the company.

You see, not only did Imation release financial results, but the same day, the company acquired the recordable media business of TDK in a $300 million deal. The combination itself makes plenty of sense -- TDK has a well-known and liked global consumer brand, while Imation has the hardcore technical know-how and product quality to impress uber-nerds like myself. And, the purchase price seems affordable, especially as a 90% or more stock-swap structure. Historically speaking, Imation doesn't often trade in the upper $30s per share like it's doing today.

The timing is interesting, too. Making a push into consumer-oriented branding only days after adding a brand management expert to its board of directors (Geneva Watch Group CEO Mark Lucas, with a background in marketing for Gillette, Duracell, and Nestle) can't be a mere coincidence. Imation will be interesting to watch from here.

Don't you hear the whistle blowing?
Rise up so early in the morn.
Don't you hear the captain shouting
"Dinah, blow your horn?"
-- "I've Been Working On the Railroad," Traditional

At the last stop, we'll buck the downbeat trend. Eastern railroading colossus CSX (NYSE:CSX) may have missed the $0.53 analyst earnings target by $0.03 per share, but the market liked what it saw and boosted the stock price by 5% the night of the report. What's the story?

The company raised shipping prices by 4%, while volume fell by about as much. While that sounds like a break-even situation, it also means that the costs of delivering similar-sized revenues just went down a bit, so it's a strong operational showing.

Management also indicated strong expectations for the rest of the year -- volume should pick up, and there's another round of aggressive price increases on the way.  But the real boost seems to have come from another SEC filing that day, saying that an activist hedge fund plans to increase its stake in the company by $500 million.

Berkshire Hathaway (NYSE:BRK-A, BRK-B) CEO and master investor Warren Buffett recently took up positions in three U.S. railroads, so there's plenty of capital and investor interest pouring into the industry right now. In contrast to our other underachievers this week, CSX shares have never been this pricey, making a purchase of this stock less of a value play and more a vote of confidence in operational excellence. I wish my former employer the best of luck, but I won't buy the stock at these prices.

They fight over juice in their Terrible Twos,
But some daughters and sons start with Terrible Ones!
           --Anders Bylund

If I don't make sense today, please refer to the verse above -- it explains my lack of rest, even on the weekends. Likewise, some of these underperformers are victims of larger circumstances, while others might have only themselves to blame. It's up to you to decide which down-on-their-luck companies should be able to pull themselves up by the bootstraps and which really are stuck in the mud. Come back next week, and we'll take a look at another batch of mishaps and disappointments. It'll be fun and educational, and for the last time in a long while, a little bit poetic.

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Fool contributor Anders Bylund is an AMD shareholder but holds no other position in the companies discussed this week. Once upon a time he really did work for the railroad. The Fool has a disclosure policy, and you can see his current holdings for yourself.