Perception and Reality are often the same thing. But in marketing illusions are created. We all are governed by our perceptions of what we think we know, rather than what is. Most doctors will irrevocably form an opinion if the prescription they write “bounce” back, even if only once. This could happen because the chemist, feigning unavailability, substitutes the brand but the deed is done and doctor will carry a life-long impression about the unavailability of the product which he/she will communicate to the company Medical Representative (MR) time and again. What an interplay of perception and reality.