Please see my answer for the "after life" question"...i think it is explained there.

On each of the 7 mansion worlds, we are being cleaned up of our old thoughts that do not relate to a loving Father and a loving brotherhood (so, it is best to do that here - and THAT is the value of the UB!), as we are also being purified, being prepared spiritually to better blend/bond/fuse with our indwelling Father Fragment who SO craves for us to do so, as he NEEDS our personality and mind to complete his "project" with us! 

There will be SUCH a great adventure on each mansion world and on the worlds beyond. And we are told that all of the dreams we have of travel which we could not do here on earth, will be fulfilled BEYOND our greatest imagination!