Just last night I was searching through images of old newspaper articles online when I came across a photo of two young men who were serving in the First World War. It should have been a wonderful treasure but instead the photo was almost completely black due to the way it was microfilmed. This is the rule rather than the exception when viewing old newspapers on microfilm -- and in most, if not all cases, the original newspapers were destroyed after they were microfilmed. This is the case for articles and photos that are of personal interest and also of historical import.
Even records that have been captured more recently using more modern technology often come up short because they were done in bulk by people who had to meet a deadline and therefore couldn't afford to fidget and fuss with each image. And if you don't have the originals to go back to, you might be stuck with unreadable documents, which again might be relevant to a few individuals, or to the world at large.
Regards,
Josephine