Is one where the agent/editor tells the author exactly why her work was not accepted. Granted, I understand the numerous rejected projects do not feasibly allow for everyone to get one, but as an author who is trying to make it, I...kind of need them. I just got a helpful rejection letter for Trolling Nights; and while I am not pleased the project was rejected, it made me feel a whole lot better to know why it was--and furthermore, that adage that it's "not the right fit" really is true. Because, as many authors know, regardless of their success, form rejections don't do much to help maintain what (sliver) of self-esteem we have. When everything you've written is constantly rejected, at some point an author beings to think it's not the project, it's the producer. But what made this a first, especially, for me was the invitation to submit directly to this editor should I have another project I want to submit because she sees potential in my writing.
THAT...yes. Almost balanced out the "bummer!" feeling of the rejection in the first place.
Just the knowledge you are not awful is half the battle. Now, the other half...probably the HARDER half...writing that story that people want to sign on, that people, other than the author, believes in. I haven't done that yet, or I haven't submitted to the right people yet, but I have so many stories being written or need to be written that I hope one of them is the one. Or else, Lulu and I will be close and intimate bedfellows!
ETA: I got another one, this one not so helpful, and from an agent, but that's all right. It's becoming clearer to me and I should just stop fighting it, I think.