One thing I've realized lately is that as a doctor, it helps immensely to be outgoing. It also helps in life, but especially in medicine.
I don't think I'm naturally outgoing. I'm not introverted either, but maybe something in-between. Like if there was a 10 point scale where 1 would be a computer programmer who works at home and has Asperger's, and 10 would be, like, Jim Carrey, I'd be a 5. Or maybe, at best, a 6.
If you work in an office, there's usually a constant set of coworkers and staff that you can get to know over time. But in most fields of medicine, you're constantly meeting new people, both patients and staff. If you're not good at it, people won't like you as much.
For that reason, even though I'm a 5, I really try to make an effort. But it's hard.
When I was a fourth year med student on an away rotation at an outpatient clinic, I started one week before another student named John. Within a day or two, John knew the names of all the staff at the front desk and was friendly with them. I'd been there over a week, and I barely knew who they were.
It's entirely possible the staff thought I was too big a snob to get to know them. But that wasn't the case. My natural instinct is that I feel too shy to just go up and start introducing myself to all the staff. But I still think it ended up reflecting badly on me.
The same is true when meeting new patients. If you're nervous about meeting new people, patients may also see you as cold and unlikable. I recall doctors I've seen as a patient that I didn't like, and many of them were probably somewhat introverted.
I guess my point is that if you're an introvert, you should probably either avoid medicine, or choose a field that doesn't involve much patient care.