Not much to add to whats above/already written on this forum.
I've had multiple friends DOR/attrite/med/legal out of various stages in the pipeline. Two were separated. One for extenuating health reasons. The other was due to extreme personal life circumstances. The rest stayed....whether they wanted to or not.
In short, you DOR or they attrite you. You do some research then submit a "POCR" (redesignation) package a couple of months later. Then a couple months after that, your new community contacts you. Detailers start writing orders and you'll head out to whatever is next.
I had a slightly differing observation than Fink, unless it was a legal issue, how someone was removed from the pipeline seemed irrelevant when it came to opportunity. Plenty of performance attrites/DORs moved into competitive designators. Just because flight school wasn't a fit doesn't mean you're a bad officer.