I was thinking that I probably ought to tell the story of co-brands over the past twenty or thirty years, and that the respective terms "proliferation" and "convergence" might serve such a story well. I made a general and more or less obvious observation: that brands have proliferated over the past twenty or thirty years. Once this observation was made, I could tell two basic stories to explain it, based on the two terms mentioned.

First, I might say that brands "proliferated" in the 1980s and 1990s, only to later "converge" through the practice of co-branding. This story has the benefit of explaining why co-branding emerged in the late 1990s and 2000s as an increasingly viable marketing strategy: to reduce brand clutter.

However, I could also point out that a great deal of brand "proliferation" in the 1980s and 1990s was in fact the result of single companies extending their product lines. For instance, the Coca-Cola Company has developed and introduced a mind boggling number of brands both in the USA and globally over the past two decades. These brands have already "converged," more or less, under the Coca-Cola umbrella brand.

Co-branding, in this story, represents an attempt to "proliferate" these internally produced brands by extending them to other product categories. In other words, actual brand extension, rather than simply product line extension. This story has the benefit of also explaining why large corporations have begun seeking out co-brand partners.

You see the paradox of telling the story of co-brands.