What would it take for Twitter to be part of the mainstream?
That's what I wondered after the company's shares plummeted last week following its second earnings report as a public company.
The microblogging site reported that user growth in the three-month period that ended in March was 25 percent, down from the previous quarter's user growth of 30 percent.
In addition, another key metric -- the number of times users refresh their pages to look at tweets -- grew by 15 percent. But that was also down from 26 percent and may be a sign that users are less engaged with the service.
Last week, Ben Schachter, an analyst with Macquarie Capital, wrote in a note that Twitter, valued at $30 billion, "must reaccelerate its user base if it is ever to grow into its valuation." The competition is stiff and it's not clear how the company can do it, he said.
Twitter CEO Dick Costolo told analysts that the microblogging site has already become part of the mainstream, countering the impression that it's a hangout for elites and influencers who like to talk to each other. As evidence, Costolo said that tweets from the Academy Awards show were viewed three billion times.
It's true that Twitter handles are woven into every news, sports and entertainment event. But that doesn't mean the masses are jumping on Twitter to engage.
"Twitter is struggling with understanding what it is and what it wants to be when it grows up," said Debra Aho Williamson, an analyst at eMarketer, a market research firm.
In a December column, I said Twitter is a chaotic, confusing service that is daunting to many newcomers and that it needed to do more to make it easier for people to join and figure out how to use it.
And that continues to be an issue.
But there may be a bigger issue than bringing in more people to try out the service: Making sure that Twitter is essential to users, something they really can't get anywhere else.
Facebook users swear that the service is critical, a way to check in with their many social circles, as well as share and find interesting news.
LinkedIn has carved out a critical niche as the professional network.
Even new sites like Secret and Whisper have found their calling as the places to go to hear underground conversations.
But Twitter? It's a jumble of voices that are part of a network of very loose connections.
Some people like Twitter's channel surfing aspect, the randomness and the rabbit holes they fall into.
But for others, Twitter offers all the downsides of channel surfing, without the payoff. Many just give up.
Brian Wieser, a senior analyst at Pivotal Research Group, is not convinced I'm right about Twitter's need to expand dramatically.
"It's just not for everyone," Wieser said. "Users are not the important metric to focus on. Of course, you don't want them falling off a cliff." What's more important than users is how the service is delivering to advertisers, he added.
But I am sure Costolo cares about the number of users and user engagement. That is key to advertisers. Becoming mainstream instead of a kooky outpost or a place where the elites chatter has to be Twitter's end goal.
What is going to be Twitter's unique calling card? It can't just be the water cooler anymore. On any given hot topic, my Facebook friends are having the same discussion as the people I follow on Twitter.
I don't know how Twitter should become mainstream and really accelerate user growth and retention.
But it needs to find a way to be essential to those who give it a try.