In the past few weeks, the stocks of the two leading social media companies have had turbulent rides. After their last quarterly earnings reports, Facebook suffered the largest single-day loss in market value in US stock market history, while Twitter's stock plunged more than 20 percent. Can these tech giants get back on track? CGTN's Mark Niu has the details.  

Taking a beating on the stock market and in the court of public opinion, in recent weeks Facebook and Twitter lost billions of dollars and millions of accounts.

MATT SWANSON, MANAGING PARTNER SILICON VALLEY SOFTWARE GROUP "I think part of it is a shift in consumer behavior away from these sort of public broadcasting to intimate private messaging. That shift has really become dominant so that traditional social networking growth has tapered off."

Swanson is a serial startup founder and managing partner of Silicon Valley Software Group. He says even though Facebook's growth is slowing, many users have shifted their attention to platforms like Instagram and WhatsApp both of which are owned by Facebook.

MATT SWANSON, MANAGING PARTNER SILICON VALLEY SOFTWARE GROUP "We're seeing a shift into these new channels, but again Facebook owns them. We're gonna see Facebook have to figure out how to monetize in these channels. Facebook, again, they've been strategic about how they have maintained the channels that consumers are flocking too. Twitter doesn't have a similar story."

RAY WANG, PRINCIPAL ANALYST CONSTELLATION RESEARCH "Twitter's problem is their user accounts are dropping, and they are basically in a fight for what is news and what is authentic."

Twitter, and Facebook, too, recently had to purge millions of fake accounts.

RAY WANG, PRINCIPAL ANALYST CONSTELLATION RESEARCH "And the question is, is it their job to police speech? Is it their job to provide a safe environment? But by reeling in a lot of fake accounts, a lot of bot accounts, what they were able to do is address a big portion of the problem."

MARK NIU SAN FRANCISCO "Facebook has been raked over the coals over privacy scandals like when the firm Cambridge Analytica gained access to private information on up to 87 million Facebook users. And now it has to contend with the new General Data Protection Rules from the European Union, which sets out stiff fines for companies not gaining sufficient consent to use a customer's data."

Zuckerberg says: "It was my mistake and I'm sorry." 

RAY WANG, PRINCIPAL ANALYST CONSTELLATION RESEARCH "Facebook's fundamental problem is that they'll be doing apology tours for quite some time if they believe that data is free and that privacy does not exist. And I think those are the two things that power what they do. Now on the other hand, it's a free service. You are paying with your data, so it's not really a free service, and I think that's what their understanding is."

MATT SWANSON, MANAGING PARTNER SILICON VALLEY SOFTWARE GROUP "Facebook did this with their users to ask them alternative business models. In the backlash from their data privacy. It was almost an infinitesimally small number of people who were even willing to pay a dollar a year for the service."

As he scrolls through his Facebook account, Swanson is amazed out how many ads now show up in his feed.

"Ad you don't even notice it but every sixth post is an ad. Isn't that incredible?"

Behind each of those ads is personal data that's been collected and used to target a user. Ironically, what fuels a social media giant's success is also the same thing some investors believe could lead to its downfall if not handled properly. Mark Niu, CGTN, San Francisco.