The term "Graveyard Shift" has a fairly dismal origins story.  The story begins in the early 1800's, a time when cemeteries had a night watch man whose job was simple, listen for ringing bells.
Other Facts

The term "Graveyard Shift" has a fairly dismal origins story. The story begins in the early 1800's, a time when cemeteries had a night watch man whose job was simple, listen for ringing bells.

When cemeteries ran out of room and they had to dig up old graves to make room for new ones, people began to notice something unusual. there were a lot of coffins that had scratch marks on the inside

The term "Graveyard Shift" has a fairly dismal origins story. The story begins in the early 1800's, a time when cemeteries had a night watch man whose job was simple, listen for ringing bells.

When cemeteries ran out of room and they had to dig up old graves to make room for new ones, people began to notice something unusual... there were a lot of coffins that had scratch marks on the inside!

Before the age of modern medicine, it was sometimes difficult to differentiate between a coma, or other aliment, and death; which led to people being buried alive from time to time.

One of the most common ways people tried to prevent this from happening was to tie a string to the deceased finger/hand and attach that string to a bell that would be placed on the surface directly above the grave. If they awoke after being buried, the bell would ring and they would be dug up before they suffocated.