Note to self: If you ever go public, forget about growing your business, increasing market share, and other irrelevancies -- just make sure you hit earnings estimates, or else ...

Or else you just might wind up like recreational vehicle and manufactured housing company Drew Industries (NYSE:DW) did yesterday. The Motley Fool Hidden Gems pick reported earnings had fallen a good $0.10 short of analyst expectations of $0.91 per share in profits this quarter. When Drew 'fessed up to earning only $0.81, stock traders threw their predictable hissy fit, bidding Drew's shares down 5%. Overreaction? Underreaction? Let's consider the facts.

On the top line, Drew grew its Q2 2005 revenues 15% over the year-ago quarter. Year to date, Drew's sales are up 27% over the first six months of 2004. Sound good? It gets better. Along with those sales climbs came an increase in the company's already dominant (greater than 50%) market share in providing components for manufacturers of RVs and manufactured housing.

Unfortunately, somewhere along the road, Drew's profits trailer came unhitched from its revenues cab. Year over year, second-quarter profits grew less than half as quickly as did sales, up only 6%. While that's better than the 3.5% decline in earnings Drew tallied last quarter, it's still not the kind of result that impresses the Street.

Another thing that apparently doesn't impress the Street is investment in the future, such as the $850,000 Drew spent starting up its Arizona window factory this quarter. Remember back in January when Motley Fool Stock Advisor pick eBay (NASDAQ:EBAY) promised to spend $100 million building its business in China? If you owned the stock, if you endured the sudden, gut-wrenching 20% plunge in market cap that followed that news, I'll bet you remember it.

Drew's stock didn't fall quite as precipitously. But then again, this little Motley Fool Hidden Gem has only four analysts following it, most hailing from small-fry financial institutions. This is in direct contrast to the 24 big-time, big-bank analysts who screamed "fire" in Wall Street's theater of investing upon hearing eBay's news.

Perhaps Drew's investors should count themselves lucky that they're not being followed by the likes of Piper Jaffray (NYSE:PJC), Deutsche Bank (NYSE:DB), and Friedman Billings Ramsey (NYSE:FBR), all of whom downgraded eBay for investing in the future, all of whom looked a little foolish (note the small 'f') last week.

And as for the analysts, they might also draw a lesson from eBay's performance. With Drew reversing last year's negative free cash flow to generate $8.5 million year to date (excluding any acquisitions of businesses), its market share growing, its production capacity expanding, and its sales booming, downgrading this stock might well be similarly foolish.

Fool contributor Rich Smith owns no shares in any of the companies mentioned in this article.