Waitlists

Can somebody please explain? Are these for just popular models or all watches? My dad pissed off my mom (5-10 years ago) and she just went to an AD and bought one new. Is that not usually a thing.

Like MAYBE I’m misremembering this but I could’ve sworn she walked out with one that day. She definitely bought it new and not used though, and it was 100% an AD because I know where she got it from.