The only thing better than buying into a great company is doing so early in its growth cycle. Initial public offerings (IPOs) are the first sale of a company's shares to the public. They give investors like you and me a shot at an early arrival -- but it's never quite as easy as that.

Many ground-floor opportunities promptly sink into the basement. Some "can't-miss" and "lay-up" IPOs wind up as nothing more than airballs.

You can help your cause by learning to spot the differences between the winners and the losers. What makes a hot IPO great? What are the warning signs of a debutante stinker? Let's dive into the answers you need.

Anatomy of a hot new stock
The best way to unlock the secrets of tomorrow's big gainers is to dig into the market-thumpers of the past. Let's take a closer look at the best-performing IPOs of 2007:

IPO

2007 Gain

JA Solar (Nasdaq: JASO)

$15.00

365%

MercadoLibre (Nasdaq: MELI)

$18.00

310%

Yingli Green Energy (NYSE: YGE)

$11.00

252%

VMware (NYSE: VMW)

$29.00

193%

FCStone (Nasdaq: FCSX)

$24.00

188%

Don't rack your brain looking for a common theme. The winners come from all walks of life. JA Solar and Yingli are Chinese makers of solar power components. MercadoLibre runs a popular Latin American consumer auction site. VMware is pioneering virtualization software. FCStone provides risk management services to commodity traders.

In short, you are unlikely to see these five companies rubbing shoulders at any particular industry trade show.

So what ties all of these hot issues together? It isn't necessarily pent-up market demand. Yingli shares actually fell by 5% on its first day of trading. Redemption came after investors flocked to the shares as a way to play the hot -- literally and figuratively -- sector of solar energy.

Sometimes a hot IPO shows its winning ways right away, of course. Longtop Financial (NYSE: LFT) went public at $17.50 last year, soaring 70% higher on its first trading day. A hot financial IPO in a subprime-shaky 2007? Yes, but this is actually a software company providing enterprise solutions to the banking industry in China. As you can imagine, the Chinese banking economy is doing a lot better than the industry closer to home. The stock has given back its gains with recent weakness in Chinese stocks, but it sure came out as a blazer.

Brands like MercadoLibre and VMware, along with investing themes like solar energy or enterprise software in China, can provide an early advantage. But these success stories wind up earning the market's faith by producing strong quarterly results early in their tenure.

Fresh winners can do a portfolio good. Two of 2006's hottest IPOs are recent recommendations in the Rule Breakers newsletter service. The growth-stock research service didn't get subscribers in on the offering price, but both stocks have beaten the market since being singled out.

So what have we learned? Hot IPOs come from different sectors, and they're saddled with different investor expectations. Will that help you land the winners from now on? It will if you accept the nuances behind the disparity. Most of the hotties came to market as quality players, then went on to cement that perception with heady quarterly growth performances.

The pitfalls of IPO investing
There are naturally plenty of dogs in any IPO litter. Glu Mobile (Nasdaq: GLUU) went public last year at $11.50 a share. It's trading at less than half that price today. The publisher of mobile games has been able to grow its top line, but it continues to post losses. Analysts expect it to see red through all of 2008.

I like to weed out the potential portfolio-killers by looking for a few warning signs.

  • Is the IPO an exit strategy? If there are too many executive insiders selling, it may be.
  • Is this an inferior company trying to ride coattails? Many investors learned this the hard way in the dot-com bubble days, when pretenders like Pets.com and Webvan collapsed. Make sure that new stocks are as good -- if not better -- than their publicly traded peers.
  • Is the valuation realistic? Underwriters often reach too high for a company where the prospects are much lower.
  • Is it a forced IPO? I hate it when a company rushes to go public as niche enthusiasm is waning. It's as if they've heard the last-call order from the bartender and are scrambling to order one more beer. Whether it's a nervous private equity firm or a cash-strapped upstart, I avoid those "me too" copies like the plague.

So, where does that leave you? The IPO pipeline is never dry. There may be fewer new issues going public while the market corrects itself, but quality ones find a way to earn their ticker symbols.

Don't let new stocks scare you. The Rule Breakers newsletter has recommended several new companies, in some cases just weeks after their market debuts. You're welcome to read up more on the reasons why we pluck 'em early for the growth service's scorecard. A 30-day trial subscription will get you in for free.

Getting in early has its risks, of course. We've already explored how that ground-floor elevator sometimes stops down in the basement. However, getting in early is the best way to enjoy the longest ride up to the penthouse.

This article was originally published on March 10, 2007. It has been updated.

Longtime Fool contributor Rick Munarriz is a fan of new stocks, and he's even recommended several fresh IPOs to newsletter readers. He does not own shares in any of the companies mentioned in this story. The Fool has a disclosure policy.