Disappointing earnings put Amazon.com shares on track for its worst day since October 2011 on Friday—but to two Wall Street analysts, the stock is struggling because investors are simply fed up with the Internet retailer's lack of revenue growth.
"This still is a large e-commerce company at its core and one that continues to take gross profit and invest it back in the business to grow," UBS analyst Eric Sheridan told CNBC. "So what investors want to see is that gross margin dollar reinvested back in the business yield a higher rate of growth, and I think that's what's giving people pause today."
Read MoreAmazon earnings miss estimates
Amazon blamed its larger-than-expected second-quarter loss on its grand investments. It said it will spend more than $100 million on original video content in the third quarter, for example, considerably higher than its spending a year ago and in the second quarter.
To Sheridan, though, investors are tired of waiting for a return on that investment.
"Frankly, [there] are a lot of Internet stocks that trade at much healthier multiples than Amazon does that are growing revenues 20 percent plus," he said on "Squawk on the Street."
Standard & Poor's analyst Tuna Amobi said Amazon has been in "perpetual investment mode." and he'd like to see the retailer begin to translate that into sustainable profitability. He currently has a "sell" rating on the stock, and a price target of $300.
"The core retail business is doing exceedingly well, both domestically and internationally. The problem is that a lot of the cash flow that has been generated has been reinvested into a lot of potentially questionable initiatives," he said in an interview with "Street Signs."
Read More Pro puts Amazon's new Fire Phone to the test
Amazon delivered a Q2 loss of 27 cents a share on Thursday, sharply missing expectations for a loss of 15 cents a share. The company posted sales of $19.34 billion, matching forecasts.
The online retailer's first smartphone, the Fire phone, becomes available Friday.
—By CNBC's Drew Sandholm, with Reuters. CNBC's Michelle Fox contributed to this report.