When Urban Meyer took over as the Ohio State head coach it was obvious he was going to let go of most of the assistant coaches. He had to install his offense with guys he thought who could coach it, and changes had to be made on the other side of the ball as the Buckeyes were coming off a losing season.
The result, Ohio State was 12-0 in 2012.
When Ryan Day took over he knew he only had to fill his old position as quarterbacks coach because he had a great relationship with the assistants and Mike Yurcich was a great hire.