Difference between useControlledState and initialState?

[PenguinDetective]

Following the documentation, you have both the initialState and the useControlledState (Source 1 | Source 2).

What is now the difference between both of them?
It seems like both achieve the same thing:

const {controlledPageIndex} = props;
 useTable({
   useControlledState: state => {
     return React.useMemo(
       () => ({
         ...state,
         pageIndex: controlledPageIndex,
       }),
       [state, controlledPageIndex]
     )
   },
 })

and

const {controlledPageIndex} = props;
const {
    getTableProps,
    getTableBodyProps,
    ...
} = useTable(
    {
        columns,
        ....,
        initialState: {
           pageIndex: controlledPageIndex
        }
    }