It was about this time last year that calls for the head of Groupon (GRPN -5.31%) founder and CEO Andrew Mason were reaching fever pitch. Groupon shareholders got their wish the following month when Mason was shown the door, kick-starting a nice run-up of Groupon's share price.

By the time Mason was ousted, it wouldn't have mattered what he'd done or how he'd done it; he became the story, not Groupon. When that happens, a change of leaders is needed, whether warranted or not, for the good of everyone. An analyst at the time put it this way: "Mason's departure is largely symbolic." There were still financial concerns, but Mason was also laying the foundation for today's Groupon.

Did he just say that?
Mason's ouster was symbolic, yes, to appease disgruntled shareholders, particularly following a dismal earnings report that resulted in a 24% drop in Groupon's share price. But Mason did more to raise the ire of the investment community, and leave them scratching their heads, to earn his walking papers.

The list of Mason's gaffes is a fairly long one. The lead-up to Groupon's highly anticipated IPO began with the SEC screaming foul over accounting irregularities that excluded marketing costs from its financials. A last-minute bump in its IPO price and increase in the number of shares offered didn't exactly sit well, either.

But it was Mason's off-the-wall comments and odd behavior that left investors wondering, "Who is this guy?" The curse-laden memo the press got a hold of during the SEC-mandated quiet period leading up to the Groupon IPO, apologizing for a break in his corporate strategy meeting by saying, "Sorry, too much beer," are a couple examples.

And let's not forget his heartfelt letter to employees announcing his departure, which included statements like, "I was fired today, If you're wondering why, you haven't been paying attention." Mind-boggling. So, given the problematic IPO, a misguided CEO, and horrendous stock performance prior to 2013, what do Groupon shareholders have to thank Mason for, other than leaving?

Setting the table
Many of Groupon's financial concerns leading up to 2013's stellar stock performance -- a nearly 140% return for the year -- surrounded a few areas. One, a number of analysts' cited "deal fatigue" as a roadblock to growth for Groupon's bread-and-butter: deals. There were just too many players and too many alternatives equated too little upside -- or say analysts said.

Another concern was how would little Groupon Deals compete with $180 billion Amazon.com (AMZN -1.51%) with its AmazonLocal deals business and its investment in LivingSocial -- yet another deals site that would stifle Groupon's growth prospects. When Google (GOOGL) missed out on buying Groupon for $6 billion pre-IPO, it did what Google does: introduced its own deals service, Google Offers. The general consensus was that with Amazon.com and Google in the game, Groupon Deals didn't stand a chance.

And here's where Mason deserves the thanks of Groupon shareholders. Recognizing that Groupon Deals was under heavy competitive pressure, and the competition was coming from behemoths like Amazon.com and Google, Mason began to set the table for the Groupon of today.

As I mentioned in an article a year ago, Mason's steps to diversify and enhance Groupon's revenue streams were spot on. That includes Groupon Goods, a business widely panned at the time  because of its low margins. But it's working. In Groupon's most recent quarter, Goods revenues were $194.6 million, up about 28% from the year-ago period. Not surprisingly, analysts point to Groupon Goods and the alternative revenue source it provides as one of Groupon's strengths.

You can add several acquisitions to improve online retail sales, location tools to better target deals and services, a low-cost merchant-services solution, and strong mobile push to Mason's foresight. Yes, he misfired in a lot of ways, but as Groupon shareholders continue to enjoy their stellar gains, like it or not, Mason deserves some thanks.