The process of decolonisation in Nigeria was a very untidy one. The British, when they were leaving finally and knew exactly who they wanted to take over, they wanted pliant government, figures, structures, they wanted to continue indirectly in effect their control over much of their colonial possessions and this was one of the very early causes of conflict.
You don't choose because if you choose you might make the wrong choice, based upon ego or illusion. Instead, you let eternity make all the choices for you.