Based on the aggregated intelligence of 165,000-plus investors participating in Motley Fool CAPS, the Fool's free investing community, online retail giant Amazon.com (Nasdaq: AMZN) has received a distressing two-star ranking.

With that in mind, let's take a closer look at Amazon's business and see what CAPS investors are saying about the stock right now.

Amazon facts

Headquarters (founded)

Seattle (1994)

Market Cap

$56.7 billion

Industry

Internet retail

Trailing-12-Month Revenue

$28.7 billion

Management

Founder/CEO Jeffrey Bezos

CFO Thomas Szkutak

Return on Equity (average, past 3 years)

30.1%

Price to Earnings (AMZN and S&P 500)

52.4 and 15.2

1-Year Return

49%

Competitors

eBay (Nasdaq: EBAY)

Overstock.com (Nasdaq: OSTK)

Apple (Nasdaq: AAPL)

Sources: Capital IQ (a division of Standard & Poor's), Morningstar, and Motley Fool CAPS.

On CAPS, 23% of the 4,871 members who have rated Amazon believe the stock will underperform the S&P 500 going forward. These bears include GearCat and Look4Dough.

Just yesterday, GearCat touched on Amazon's seemingly unsustainable valuation: "Great company, incredible CEO, great products and services! Problem is that everyone seems to have grabbed on and the rock concert is about to let out."

While most of us Fools agree that Amazon is truly an outstanding business, it's the stock's lofty price tag that our community seems to have trouble with. Currently, Amazon trades at a steep forward P/E of 36, which is more than double that of its close competitors eBay and Overstock. Although Amazon certainly deserves a premium, many Fools believe it's just too big right now to protect against any of the earnings hiccups down the road. And with tech giant Apple steadily encroaching on Amazon's e-reader turf, CAPS members like Look4Dough feel that may happen sooner rather than later:

The company is great, but the valuation now is very rich. ... [A]t $50B market cap, to double again will take a while. Plus, now there is more competition from Apple, not only between iPad and Kindle, but also more people are buying eBooks rather than paper Books, which will eventually eat up from [Amazon's] margins. True [Amazon] has a major retail online store, but there is more competition now as we have more and more online stores.

What do you think about Amazon, or any other stock for that matter? If you want to retire rich, you need to protect your portfolio from any undue risk. Staying away from dangerous stocks is crucial to securing your financial future, and on Motley Fool CAPS, thousands of investors are working every day to flag them. CAPS is 100% free, so get started!