When I started writing in the early 1970s, photocopiers were not ubiquitous. Not every publishing office had a photocopier, so multiple copies of generic rejection slips were often printed on the office mimeograph or on a printing press using hot metal type. Later, photocopiers mostly replaced mimeographs in the office and offset printing mostly replaced letterpress in print shops.
But rejection slips remained slips of paper that accompanied unwanted manuscripts home from the slush pile.
Over time we learned how to read those rejections slips. No, not the generic copy printed on them that said, in one way or another, "Thanks, but no thanks." We learn to read the implied messages.
A poorly photocopied rejection slip? Didn't make it past the intern who's being punished for accidentally insulting a senior editor's spouse.
A crisp, photocopied rejection slip? The intern actually read the first page of the manuscript.
An original, printed rejection slip--not a photocopy? The intern kicked the manuscript up to an assistant editor.
An original, printed rejection slip with one or two words indecipherably scrawled at the bottom? The assistant editor read a few pages.
An original, printed rejection slip with "Not for us" or "Try again" scrawled at the bottom? The assistant editor read the entire manuscript.
An original, printed rejection slip with the editor's name scrawled at the bottom? The assistant editor kicked the manuscript up to the editor, who read a page or two.
An original, printed rejection slip with "Not for us" or "Try again" scrawled at the bottom, followed by the editor's name? The editor read the entire manuscript.
An original, printed rejection slip with any comment related to the story--"weak plot" or "unbelievable characters," for example --scrawled at the bottom, followed by the editor's name? The editor read the entire manuscript and liked it enough to offer a few thoughts.
A personalized rejection letter that the editor took the time to type? That's almost a sale. Or the editor had too much free time, in which case the publication didn't have much of a slush pile.
Beyond that are responses that aren't actual rejections; suggestions for revision, requests for revision, acceptances contingent upon revision, and acceptances.
Today, though, all that implied information is lost to writers. With manuscripts submitted via e-mail, and responses, when they come, also arriving by e-mail, it isn't possible to easily suss out who may or may not have looked at the manuscript and what they may or may not have thought of what they read. Rejections are often cut-and-paste blocks of type with no personal touches added, and when personal touches are added, they may be nothing more than dropping the writer's name into a space reserved in the salutation and the story title dropped into another spot in the opening sentence.
And a sig line isn't a signature. It's just another cut-and-paste block of type.
Although I don't receive nearly as many rejections as I did back in the early 1970s, I miss rejection slips.