because you would think a new AD would like to hire his own "guy" and not have to deal with the legacy of Jarmmond. So, the logical progression is we fire Jarmond, hire a new AD and the new AD leads the effort to hire a new head football coach.
On the other hand, a new AD will be faced with a herculean task of rebuilding UCLA football and inheriting a head coach from a previous administration, gives him a few years of cover before the scrutiny of how successful the new AD is at resurrecting our football program.