Human Resources personnel are know to hire more of external candidates because they tend to spend less on external candidates when the expected work is being executed and they have this perception that external candidates would have more zeal to work harder than current employees so, they tend to undervalue the known ones.
This statement is true as managers would prefer to hire new employees from external source instead of promoting candidates from within. Such managers feel that the kind of skills and experience required for higher roles is better seen from people who have experience in other organizations and industry rather than their own employees. Hence at least one research study has found that manager would rather hire external candidates than promote their own employees because of the value they place on unfamiliar candidates.
