"The Kiss of Death"
In the 1970s, Michael Porter worked on the relationship between a company's market success and its strategy and found in a series of empirical studies that
companies with a very small market share (specialists) and
companies with a very large market share (generalists)
show significantly high profitability. While other competitors - with average market shares - achieve low profitability and stuck in the middle. And that is just another name for "The Kiss of Death".
A very good example is if you have a look into the automotive industry. Companies as BMW, Mercedes oder Tesla are definitely differentiators while Japanese manufacturers are clearly the cost leaders. What do you thing how GM, Chrysler fit into this? Exactly!