eBay (EBAY 0.58%) used to be the go-to place for anyone to sell their products online. However, with more options than ever before, the auction site's popularity may have peaked, and tougher times could be ahead for the company.

Let's take a closer look at how eBay has done recently and whether it has enough growth left to still be a good stock buy today.

Earnings expectations met in Q3, but forecast underwhelms

In its most recent quarter, eBay was able to meet analyst expectations as revenue came in at $2.65 billion for the period, which is what they were a year ago as well. Earnings per share of $0.67 were slightly above the $0.64 that was expected, but profit of $310 million was down significantly from $721 million in the prior year. 

Despite the numbers meeting Wall Street's estimates, eBay's stock fell after it reported earnings, which appears to be mainly the result of its forecast for Q4. For the key shopping season of the year, the company estimated that sales would come in as high as $2.82 billion, which is below the $2.85 billion that was expected. Both numbers would still fall short of the $2.88 billion eBay generated a year ago. 

A person shopping online using a laptop, a tablet, and a smartphone

Image source: Getty Images.

Many question marks surrounding the company's future

Growth is certainly a big concern for eBay as it looks to have run out of it. But that's not the only problem facing the company. It has been the target of activist investors who have been unimpressed with eBay's business and have called for the sale of some of its assets, including online ticket exchange service StubHub. 

While the company has undertaken a review of its operations, it would not comment on any decision on StubHub -- at least not for now, anyway. In its release, eBay stated that it "continues to review the role and value of StubHub and Classifieds in its portfolio to determine the best path forward and anticipates sharing an update on the StubHub business before the next earnings release." 

StubHub generated $306 million in sales last quarter, which is roughly 12% of the company's total net revenue. And while it did see growth of about 5%, that came as a result of "marketing services and other revenues" as opposed to the company's core operations, which were flat from the prior year.

The total gross merchandise volume (GMV) that was processed across both the eBay marketplace and StubHub totaled $21.7 billion this past quarter, which was a 4% decline from the prior year, and that's been the case in each of the past three quarters for GMV. One positive for eBay is that it reached 183 million global active buyers, which was a 4% improvement from the previous year. However, if users are not spending more and instead potentially spending less per transaction, it's still not enough growth for the company. 

Concerns about growth are simply too big to ignore

The question all investors should be asking today is how much longer eBay can stay relevant. With Facebook's Instagram (as well as it's own Facebook Marketplace) offering users an easy way to sell products, and Shopify allowing anyone to become a vendor and processing payments on its own site, eBay may no longer be the hub it once was for buyers and sellers. The competition is much more intense than it was in the past, and with GMV continuing to struggle, it appears to simply be confirmation that the company's best days may be firmly behind it.

At 16 times earnings and around nine times book value, the stock isn't cheap enough that investors should ignore these issues. Granted, eBay has posted strong returns this year, with the stock up over 20% year-to-date, and last year's epic decline in the markets was a big reason for that as it gave the stock a lower starting point. Over two years, eBay shares are actually down around 2%. 

Things may not be getting any easier for eBay. With profit already falling, investors shouldn't get too comfortable with this stock. Unless eBay can turn things around and get GMVs headed in the other direction, this is a tech stock that investors may want to steer clear of.