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 homebuilder KB Home (NYSE: KBH) fell 16% today when it found out its homes and shares were built on quicksand.

So what: The Street was expecting a loss when KB reported quarterly results, but it wasn't supposed to be nearly this bad. Net loss rose to $68.5 million, or $0.89 per share, up from $0.40 per share a year ago and topping estimates of a $0.31 loss.

Now what: Some of that can be blamed on a $20.6 million charge to write down land value the company thought it was buying cheaply. I guess the housing market isn't anywhere near a recovery based on these results, and things may still be getting worse. I would stay away from homebuilder shares because I think losses will keep piling up as the housing market stagnates over the next few years.

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