Make no mistake: Amazon.com (NASDAQ: AMZN) is an online retail powerhouse that's disrupting the entire retail space, and as a stock, it has a lot of bulls. But it would be irresponsible if we talked about a stock as frequently discussed as this one without discussing the very real bear aspect, too.

In this video, Motley Fool analyst Joe Magyer discusses Amazon's almost prohibitively high cost based on its high ratios, and how other companies with their own online ecosystems -- such as Apple (NASDAQ: AAPL) and Google (NASDAQ: GOOG) -- won't be the pushovers that Barnes & Noble (NYSE: BKS) was, even despite how efficiently Amazon has been beating traditional retailers and building its moat in the e-commerce sector as the first mover.

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