Another point should be added:
Putting items on display always means additional stress for the
objects:
transport, light, dust etc. Most of the circumstances can be
controlled better
in a storage. Take leather or textiles for instance that are best
stored flat
in a drawer or hung across a  semicircular board -- what a boring
display that
would give! Preservation of objects is one of the main tasks of
museums,
whether one likes it or not.
And then there are -- at least in anthropological museums --
sacred objects
that should not be displayed at all...

Henry Kammler