A single collection of butterflies and moths may contain ten cabinets, each cabinet with ten drawers, each drawer with one hundred specimens. That's a lot of pinned insects to deal with. All objects in museum collections are important, but in many disciplines their level of importance is relative or subjective. There is no absolute way of determining whether a painting is the most important piece in the world or the essence of a particular school, although many people may have an opinion. In the natural sciences there are absolutely important specimens.
Type specimens are the embodiment of species, both living and extinct.
All organisms of a species are defined in terms of the type specimen. Each type specimen is unique, globally important and at the core of scientific research. It is an international obligation to ensure that type specimens are properly cared for and recorded. At the regional and local level voucher specimens that prove, or vouch for, records of the occurrence of species in a stated location are essential for understanding local conditions and environments. In each of these cases the importance of objects is not in question, and not at the whim of fashion.