Terrible true tales from phone support!

Me: Hello, how can I help you?
Customer: Hi, we're having a problem with our tape, it won't eject...
M: Ok, let me log in and take a look...
*Log in, look around, find the problem*
M: Looks like your media didn't mount due to a service error. I've canceled the backup, so you should be able to eject the tape and put in the new one.
C: So then we didn't get the Friday backup?
M: No, it failed, but once the new tape is in, I'll reschedule it to do the full tonight.
C: But what about Friday's data?
M: Those changes will be included in tonight's full backup.
C: But we need the Friday backup.
M: Tonight's backup will include it, so it will be backed up. Can you eject the tape?
C: Ok hang on...
*overhear him talking to someone else*
Other customer who obviously had english as a second language: This won't work because last Friday was end of month!
M: I'm sorry?
ESL: We do tapes at end of month to storage, and we need Friday's data!
M: If you eject the tape, and put in the one you were going to put in anyway, I can make sure Friday's data gets onto that tape.
ESL: But that will be today's data, not Friday's!
C: She's right, I totally forgot, we need that end of month tape.
M: ... But Friday's backup failed. I can get you that data tonight if you swap the tapes.
ESL: But if we swap the tapes then today's backup will be on there!
*carefully weighing the potential outcomes of continuing this call*
M: You know, you have a good point. I didn't even think of that. Let me get you to your field engineer. He'll be able to help you because he's more familiar with your systems.
ESL: Finally! Thank you!
C: Yes, thanks for knowing when you're over your head.
M: Oh, I know when that happens.