Practice makes perfect?

Technological innovations, especially the use of laparoscopic
procedures [for stomach surgery], have made for considerable gains in safety and efficacy.
While the operation is still dangerous in some circumstances – one
study found that for a surgeon’s first 19 bariatric operations,
patients were nearly five times as likely to die than patients that the
surgeon later operated on – the overall mortality rate is now in the
neighborhood of 1 percent.

That is from Dubner and Levitt, the full story offers much more, mostly about weight loss, and here is further discussion.