What I believe is negative about social media, is what people may believe is a lie or true. There are a lot of individuals that I believe is portraying to be someone else online than who they really are in person. The show "Catfish" on MTV is a perfect example of people impersonating someone that they are not. A lie like that will definitely create hurt and trust issues to the person that was lied to.
My advice for those who are looking to join or are already have joined social media, is to only have fun with it and don't take anything serious!