Research shows that internal CEO candidates have significantly better outcomes in terms of performance and longevity in the role compared to external hires. Internal hires have longer average tenure (8.7 years vs 7.3 years) and are less likely to be terminated than their external counterparts (24% vs 30%). Additionally, promoting internally boosts employee morale and retention throughout the organisation, and has a positive effect on how staff view the company.
External hires are usually more expensive (+18–20% salary), require longer onboarding periods and have higher exit rates and lower performance evaluations in the first two years, in particular.
One exception where an external CEO candidate may be beneficial is when there is a need to make large changes to the organisation. Typically, this is easier to achieve with an outsider. However, in most other cases, an internal candidate is advantageous due to their existing relationships, inside knowledge of the company, and lower costs and time to onboard effectively.