The concept of Critical Mass originates in physics; it refers to the volume of a nuclear product required to sustain a chain reaction in a nuclear explosion. However, critical mass in marketing requires a very different product – users – to ensure a “chain reaction” of sales.The idea of critical mass has been present in social sciences for a long time; though the term critical mass is a relatively recent adoption. The concept was originally used in the 1920s to describe the spread of disease. An infection in a population which had not reached critical mass would be one that would eventually fizzle out but if it reached critical mass it would quickly spread from person to person and be nearly...