I would think there is a trade off between how current
your cube data is and how many resources you want to
consume. I have about 10 cubes showing different
production data and some are processed every 3 hours. The
problem with processing them more is that it takes up
resources on my datawarehouse server. This impacts the
queries and drillthroughs that other users are doing.
Cubes should ideally be used for big picture things where
you don't need up-to-the-second current data. But users
want what they want...