The Shoe Button Complex is a mental model coined by Charlie Munger and Warren Buffett used to describe when an individual’s success in one area leads them to believe they know everything there is to know about all other areas.
Munger’s grandfather had managed to corner the market on shoe buttons back around 1900. The grandfather exercised a virtual monopoly over their production and sale. Emboldened by his business acumen, the old man grew to believe that he not only knew more than anyone about shoe buttons but that he knew more than anyone about anything — and he preached and proclaimed at length on such. Munger and Buffett named the syndrome the Shoe Button Complex, and they encountered it frequently in their dealings with successful business practitioners.
Identifying the shoe button complex can help you understand the intentions of others, work more effectively with successful people and most importantly, keep your ego in check.