a) Audience growth
The Digital Age removed many of the barriers to publishing and signaled “the transfer of the tools of production into the hands of people previously known as the audience,” who now became co-producers of content, including news—a role and work practice that can also be called produsage.
b) The emergence of social media
Twitter and Facebook as pillars of social media, influencing the professional practices and identities of journalists (especially in relation to verification, audience engagement, and the collision of public and personal spheres that occur on social platforms20), as well as the distribution of materials. In these networks created by individuals who trusted each other, the distribution of information from friend to friend (especially on Facebook) began to challenge traditional methods of distributing materials. Users managed the flow of materials and information themselves – including materials from news agencies, journalists and other trusted sources of information – without intermediaries. As a result of this distribution across ‘networks of trust’ (users and friends), inaccurate, false, malicious materials, as well as propaganda materials masquerading as news, began to spread more and more. Researchers have found that materials with emotional content and those shared by a friend or relative are more likely to be re-distributed on social media.
Causes of distribution:
• Increasing the chances for disinformation and misinformation to spread virally as a result of the amplification of distribution by 'networks of trust'27 and emotional reactions (which can be caused by confirmation of prejudices).
• The ability of governments and other institutions to bypass scrutiny and verification by the news media by 'going directly to the public' to avoid oversight. There is evidence of increasing levels of power manipulation of social media by those seeking to influence election outcomes and public policy.
• The difficulty of retracting or correcting cases of disinformation and misinformation once they have spread virally – no matter how hard one works to unmask them, or to report on the exposure of a hoax, the impacts and consequences of a fabricated report, a misinforming meme, a propaganda video sold as news, or an erroneous report resulting from a lack of verification cannot be completely eliminated.
• The need to publish immediately on social platforms can lead to the inadvertent sharing of misinformation and disinformation or material from unreliable sources.
• Low level of media and information literacy, and weak fact-checking skills of the general public. This means that in many cases, social media users are unable to assess whether a piece of material is true or not before sharing it with others.
• The risk that governments will erode freedom of expression from within through censorship or unjustified closures in response to the urgent problems presented above.
• The emergence of filter bubbles, which theoretically confirm personal biases and limit exposure to quality and verifiable information.
• The risk that substandard work practices and journalistic products will further weaken audiences' respect for the profession and lend legitimacy to attacks on the news media by those seeking to silence critics.
• The risk that the audience will be disoriented and unable to understand what constitutes news, or fail to recognize disinformation masquerading as news.
• Lack of preparation by newsrooms to respond to disinformation, and the need for social media editorial teams to develop new strategies to deal with these problems.
source: Journalism, 'Fake News' & Disinformation: A Manual for Training and Educating Journalists