Some companies just plain shouldn't be public. Plug Power (NASDAQ:PLUG) is one of those companies.

I don't mean to say that Plug shouldn't be "public" in the sense of offering full and complete disclosure to investors. Plug should be, and it does do, that. I mean Plug shouldn't be "public" in the sense of making its shares available for purchase by small investors who all too often don't know what they're getting themselves into. And Plug does that, too.

Nor, by the way, do I mean to pick on Plug in particular. For most of the reasons described below, I don't think Millennium Cell (NASDAQ:MCEL), Ballard Power (NASDAQ:BLDP), FuelCell Energy (NASDAQ:FCEL), or Hydrogenics (NASDAQ:HYGS) should be public, either.

On Wednesday, Plug released its latest round of quarterly results. As usual, they were the opposite of what an investor usually wants to hear. The company lost money and saw its revenues cut by more than half. Expenses increased and cash burn accelerated year over year, and current shareholders were diluted out of another 7.5% worth of their ownership interest.

If any of this came as a surprise to investors, they have two people to blame. First, there are the overly optimistic Wall Street analysts, who predicted just a 10% decline in sales and a much narrower loss. But once they're finished cursing the analysts, investors should head to the nearest mirror, and blame themselves . because they clearly didn't do their due diligence before investing in Plug.

What am I talking about? Well, I took a few minutes to leaf once more through Plug's most recent 10-K filing with the SEC and, in particular, through the "risks" section, in which Plug outlines all of the reasons an investor should think twice before investing his or her life savings in the company. Here, for the benefit of those who haven't seen this before, are a few choice excerpts, with accompanying translations into English and bracketed context where necessary.

  • "We are a development stage company." Translation: We're an R&D shop. If you're looking for profits, look elsewhere.

  • If we are unable to develop. commercially viable . products [in addition to GenCore], we will not be able to generate sufficient revenue to become profitable.

  • [Since setting up shop, we] have not achieved profitability in any quarter since our formation. . [Instead, we] have incurred losses . of $407.1 million .and anticipate continued losses for at least the next several years.

There you have it, folks, in black and white. Plug Power laid out all the risks. If you were surprised by Wednesday's numbers, don't blame the company -- blame the analysts, and bookmark the SEC's website. A mistake is only really a mistake if you don't learn from it.

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Fool contributor Rich Smith does not own shares of any company named above. One of his first calls on Motley Fool CAPS, on Aug. 21, was to rate Plug Power an underperformer. To date, this rating has beaten the S&P 500 by 14.45 percentage points.

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