If the business/function is in a relatively constant and predictable growth environment that is stable, there is no need to have more than 15% of leaders in the top right hand zone. The rate of growth of leaders will match the demand created by the rate of change in the environment.
If the business/function is in negative growth environment, and this may be for a number of factors, e.g. technlogy is reducing the need for headcount, the customer base for a particular product or service is declining, then there is no reason to have more than 5% – 10% of leaders in the top right hand zone. Too many leaders in this context will lead to the loss of talent because there will be nowhere for them to go.
Note: These distribution ideals are more relevant to functional areas than to an entire business, but can be used for multi-national business that need to manage different rates of growth in different regions or countries.