There are several different levels to answer this question as it applies to my sixty years on this earth.
There was my pediatrician in the 1960's who made multiple intrusions into my young rectum. My anus was still pretty tight back then and his finger not only seemed huge, but he seemed to stay inside me for what seemed to be an eternity(probably less than a minute in reality.)
During my twenties, I had a doctor who I believe had a Masonic ring on his index finger. He only nailed me once, in my twenties, but it was memorable.
In my thirties thru fifties, I had a female doctor. She was quick and to the point. She did the deed at 35, 40 and every year after 40.
I started going to an internist from 50 to 56.He did a rectal every year and also sent me to a gastro guy for a colonoscopy at 50 and 55.
When we moved after I retired, I had to find a new internist. He is a very nice young man who iis more into blood work and other tests than examining, I go every three months because of diabetes, but once a year I get the gown and the finger. I have become so used to the routine, that I barely feel it.
Had a colonoscopy and by my count, I was fingered three times before the procedure.