Social media and other addictive Internet sites - people are constantly glued to them, even on their work, which decreases their productivity. Social media also cause depression in many people, because they not only procrastinate, but also constantly compare their life to others, which leads to dissatisfaction. Also social media are good at spreading lies and fakes, which can have negative effects on the economy - anti-vax panic, anti-GMO, political manipulation and so on.
Sure enough, social media is able to change one's perspective only from a writing. There are so many countries in my news that hoaxes are scattered and this has an impact on all fields not only in the economy and severely able to trigger propaganda.
But not everything from social media can aggravate the economy, social media also has a positive side. As is now everywhere ubiquitous in technology, so the development of ecomerce is increasing and the number of online transactions also increases. Many mid-level businesses rely on social media as a medium for their sales or promotions.