Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of retailer Liz Claiborne (NYSE: LIZ) tumbled 14% today after the company lowered its guidance.

So what: Operating income is now expected to improve by $40 million to $50 million, instead of the $80 million previously expected, for the second half of 2010. The reduction is because of falling same-store sales at Juicy Couture, Lucky Brand, and Mexx Europe.

Now what: Juicy Couture's tracksuits are stuck on the shelves despite retail in general improving in recent months. After Liz Claiborne posted big losses for most of the year, its turnaround is slower than most investors expected, and I see no reason to jump on the shares here. There are better names in the retail space, like Aeropostale (NYSE: ARO) for solid value or Joe's Jeans (Nasdaq: JOEZ) for the growth investor.

Interested in more info on Liz Claiborne? Add it to your watchlist.

Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings, or follow his Motley Fool CAPS picks at TMFFlushDraw.

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