I agree. Here's an example of how an original story can turn to gossip. At a party you hear a comment from across the room. As it moves from party to party you notice the comments have been changed in minor increments. These small changes on their own may seem benign, however when enough of them are added without clarification or correction, the story is forever altered.
Yes, gossip can often times grow on its own. If conversations were quoted verbatim and with clarity the risk of changing into ugly gossip can be greatly reduced. But simple words passing from person to person such as could have --changes to might have and finally drops to the complete lie --Did.