No, propagation speed is equal to viral factor. A fad is analogous to a very contagious, but a mild virus. Infected people will gain immunity after a while and

No, propagation speed is equal to viral factor. A fad is analogous to a very contagious, but a mild virus. Infected people will gain immunity after a while and the virus vanishes. This happens when a fad becomes boring and not worth sharing with other people.