It's been a rough ride for Groupon (NASDAQ:GRPN) shareholders since the company went public nearly three years ago -- significant declines have been all too common. Earlier this month, for example, Groupon shares plunged, losing almost one-fifth of their value, after the local deals giant reported a quarter that fell short of analysts' expectations.

Yet, Groupon's management remains optimistic about what it's building. Though Groupon is still not consistently profitable, it is seeing growth.

Below are five of the most important quotes from Groupon's most recent earnings call. Collectively, these quotes highlight Groupon's long-term goals and the recent changes it has made to its core business.

Groupon is a mobile-first company
Other semi-recent tech IPOs, notably Facebook, once faced doubts about their ability to adapt their businesses models to a world increasingly centered around mobile computing. Groupon never faced quite as much skepticism in this area, but regardless, it's important to note that the company's mobile presence is growing nicely. During the company's recent earnings call, CEO Eric Lefkofsky emphasized the company's mobile reach. 

Nearly 92 million people have now downloaded [the Groupon] app...Mobile remains over half of our business...Mobile mix, as measured by transactions, continued to increase [last quarter], reaching yet another all-time high...We are no longer becoming business, we...are a mobile business.

Unlike other firms that depend on advertising revenue, Groupon's business should not be dampened by the shift to mobile. In fact, as more consumers download the app, Groupon may be poised to offer better deals based on, among other things, location data, and sell more often to regular app users.

Revenue continues to grow
On a GAAP basis, Groupon has not been consistently profitable anytime in its history as a public company. Even using adjusted numbers (excluding stock-based compensation) Groupon is barely turning a profit.

Investors, then, buying Groupon are likely doing so more for its long-term potential rather than a steady, established stream of income. In that respect, Groupon continues to experience revenue growth, lending credence to such an investment thesis. During the most recent earnings call, Lefkofsky summarized Groupon's recent growth.

[Last quarter] gross billings increased 29% to $1.82 billion, and revenue increased 23% to $752 million.

Is Groupon becoming a Yelp competitor?
During the earnings call, Lefkofsky talked at length about "Pages" -- a recent initiative to improve the Groupon website.

Pages sites that live on Groupon on the web...These pages...allow merchants to access our large community of people looking to buy...they have two primary purposes: One is [that] merchants can put up the kind of information that consumers want to see...[the second is that] our customers [can] leave tips.

Groupon Pages (see an example here) bare an uncanny resemblance to Yelp's local listings. However, Groupon's management insists that Pages are not intended to be used as a rating or review platform, but rather, to drive further engagement. Tips left by customers ("the service was really good") can increase the value of Groupon's local offerings, creating a sort of stickiness among Groupon's userbase.

Establishing a commerce platform
Arguably, the term "daily deals" no longer applies to Groupon, as the company has, over the last few years, moved away from the daily email blasts it was built on. Now, Groupon serves as platform for local, featured deals that may run for several days or longer. During the question and answer portion of the earnings call, Lefkofsky summarized Groupon's overarching ambitions.

We're trying to go one step further and actually connect and build a platform, and really get not just 100,000 merchants, but hopefully, one day a million merchants or two million merchants or more that are connected to Groupon all the time.

The growing popularity of its mobile app, the addition of the aforementioned Pages and other measures, are slowly shifting Groupon's business from one based around emailed coupons to a platform centered around connecting local merchants to customers. Investors interested in Groupon should view the company's potential in that context.

Groupon's long-term goals
Lastly, and perhaps most importantly, Lefkofsky offered a clear definition of Groupon's goals. 

[Groupon] define[s] long-term success as both gross billings and gross profit growing at least 20% annually over the next five years.

If Groupon can execute on both of these goals, it could create significant shareholder value. However, such targets may be overly optimistic -- although its gross billings (up 29% on an annual basis last quarter) are growing, it simply isn't generating much profit -- gross profit increased less than 2% last quarter on an annual basis.