We estimate that nearly half of the theatrical-length motion pictures made in the United States are lost forever. Consider the enormity of this loss for the historical study of cinema. It is difficult to construct even a hypothetical analogy on the same scale in another branch of history. To do so we would have to propose, for example: What if two-thirds of all the paintings done in the twentieth century were destroyed, and most of the remainding one-third were saved through happenstance rather than through systematic preservation?Well, for all we know, two-thirds of all paintings painted in the 20th century were destroyed. Not every painter is famous or later becomes famous or shows work in respected galleries or museums. Certainly work of a certain caliber has had a leg up in surviving because of fine art's consecration as a cultural good, much more than cinema's status as ephemeral and popular commodity status in the first half of the 20th century. And, yes, film poses distinct archival and preservation challenges.
But there is an advantage to this situation: we are in a position where the field has an open mind that all films are interesting on some level and worth preserving. We actually are concerned with those destroyed or lost 2/3 of cinema. Our handicap is also a strength.