Twitter's stock price continues to slide, closing today at the $26 strike price at which it went public. It closed its first day of trading around $45, a mark it has not matched since May of this year. While the company has continued to grow its revenue at a healthy pace, it has struggled to turn a substantial profit and frightened investors with its lack of user growth. CEO Dick Costolo stepped down earlier this year, and has been replaced by co-founder and former CEO Jack Dorsey. But it's unclear if Dorsey will stay on as the permanent chief, adding to overall worries about the company's health.

During its most recent quarter Twitter reported revenue of $502 million and profit of 7 cents a share, roughly double what it did during the same period a year earlier. But that same day saw the departure of several key executives, an exodus that has left the company with a number of important positions to fill. On a call with investors, Dorsey said that Twitter's failure to connect with the huge audience of people who see tweets but don't create accounts for themselves was "unacceptable."

Chief financial officer Anthony Noto phrased it a bit differently, pointing out that while 95 percent of people in most developed markets were aware of Twitter, only 30 percent used it. The company has yet to find the killer feature or simpler interface that will allow it to transition into the "mass market," Noto concluded.