Before they even know how to emotionally regulate themselves well (because at 14 we certainly don't know how to do this yet) they are finding themselves in this "always on" mode that starts a new social development. "Always on" means they have to regulate very very quickly with a lot of other stimulus and a lot of other people. While most parents regulate and teach their kids through these developmental phases, parents that aren't paying attention can find their kids lost in this overwhelming environment.
Negative side effects include a difficulty in self-regulation. If a 14 year old reaches out to seventy-five people and doesn't get any immediate responses, his feelings of isolation are exponentially increased. Mr. Oaks pointed out that as grown men, we are prone to feel profound rejection when our significant others don't respond to our needs quickly. A 14 year old is going to feel those same feelings even more intensely than an adult who has developed some emotional regulation skills.