I think for the layman, those anecdotes that strike on pathos are what sticks. I remember the stories about patients who avoid mishaps through checklists that caught the wrong limb being marked and their (understandably) irate reaction more than statistics.

This is exactly what I remember from the book.

I actually think this book is one of the rarer examples where the various stories and anecdotes that are sometimes seen (rightly) as “padding”, are actually in this case quite effective at getting the message across in quite a memorable way.

It’s been a while since I read it but I seem to recall a lot of similarly effective stories about airline pilots too.

A book needs to be read 10-15 times in order to internalize it. Otherwise, when you're in the moment, you'll forget and revert to your usual pattern.

Is there research that 10-15 times is the threshold or is that based on your personal experience?

It's based on anecdotal evidence, particularly with sales training.