People avoid sharing media which they haven’t consumed in full length as they have a harder time making sure there isn’t anything they disagrees with, let’s say at the end of a one hour presentation. Therefore, the more time-consuming a piece of information is, the less likely it is to be shared. Likewise, people avoid sharing really important things, as they are usually personal (See Worldview, Religion, Politics or tastes in Art, Literature and Music etc) and are naturally charged. Therefore, the more insignificant, bland and agreeable a piece of information is, the more likely it is to be shared. Which leads us to the conclusion that the shorter and more insignificant a piece of information is, the more likely it is to be shared in Social Media. And that’s probably exponentially related.