While it's obviously a huge red flag if multiple people quit or are not promoted in a program, a missing resident or two is hardly uncommon. I go to an extremely supportive program, but it is also very large and because of that, I'd say we're probably missing an average of one a class for one reason or another. In recent memory, one resident passed away, one had a weird situation where she was an out-of-country attending who was a fellow and then had to do residency after so started with my class but finished a year early due to accommodations, one got engaged intern year and transferred to a program across the country to be with her fiancee (and changed fields when she realized she hated pediatrics), and one worked out an arrangement to do a part-time residency and just extend the length of her training to be at home with her baby. That said, no one has been fired or not had contracts renewed despite the fact that everyone in my program could probably name a handful or so that probably should not have been allowed to advance (for both gross incompetency issues or unprofessional behavior). I don't think any of this has ever come up with an applicant to our program that I know of, and none of us would ever think to explain a "missing resident" because the stories don't seem worth mentioning (or even remembering... I had to wrack my brain for those). I almost feel like the fact a program mentions a missing resident makes it more likely there's a story behind it (unless they are just a really small program).
