Not applying broadly and no research. Most US programs have 6-9 months of research spread throughout the 3-year fellowship. Many people are surprised to know that there is a COCATS1 requirement in research and scholarly activities and it's the major reason that cardiology transitioned from a 2-year to a 3-year fellowship a long time ago. If there is an obvious blank section on ERAS under scholarly activities (not even an abstract or a poster!), it's a massive red flag. Many applicants don't realize that.
Most programs give the opportunity to do research, but I think many do not mandate it unless it’s the more hardcore research oriented programs (BWH, Hopkins, etc). Or they make you do another year or two of research anyway. I personally am spending most of the time doing clinical things which will help me in my job (nuclear, TEE, cath etc)
OP’s question re: AMGs not matching. These are the most common reasons I saw.
- no research (I know of only one person who matched without this and I suspect it was related to nepotism)
- low tier community program which has no opportunity to obtain good LORs or research or clinical opportunities
- not applying to enough programs
- weak board scores
- something dumb (incomplete app, didn’t register for the match, etc)
- bad interviewing skills and/or lack of support from home program due to personality or behavioral issues - I know of at least one person from a well regarded program this happened to
It’s no doubt true that as an AMG you have a huge advantage in the match - particularly as an MD student. However, it does not guarantee anything if you don’t apply SMART.