I will preface this by saying that there are some truly great shadowing experiences out there where pre-meds get to do/see tons of great things over an extended period of time.
That said, I believe **and I've said this all before** most of the shadowing that goes on is total BS resume filler. Now, I know someone is going to read that and get all pantybunch about it and try and flame me, but believe me, you will be wrong.
The problems I have with shadowing are:
1.) The pre-meds I've known IRL (which is no small number) tend to collect shadowing experiences just to collect them and later brag about it. Whenever a bunch of these people get together, it reminds me of a "Magic: the Gathering" tournament. "Shadowed a radiologist, eh? Impressive. But I'll see your radiologist and raise you a neurosurgeon. *Fireball! Fireball!!!*"
b.) A lot of times, it's very short-term. Maybe it's just me, but I hate when people put down stuff that they've done for like, a week, let alone a couple of hours. If I didn't put in a substantial amount of time into a project/experience, it never made it on my application.
III.) There are more hands-on/active ways of seeing and experiencing medicine. I'm not suggesting volunteer work at a hospital, because I've been there -- I know -- it's kind of dull and you don't see much. But there are tons of immigrant and community clinics that really need an extra pair of hands. The same thing can be said of senior centers and adult day cares; it might not sound as sexy, but you'll see so much stuff. There is always the EMT option or even ski/wilderness patrol if you're athletically inclined. I used my language skills to become a medical interpreter and that was total gold as I obviously saw/heard lots of things, got lots of patient contact, had to develop a good bedside manner and become adept at asking whatever personal questions the doctor needed answered.
Shadowing can be a great starting point. Just don't stop there. There are a ton of ways to become more involved and to experience medicine other than just accumulating 50 different shadowing experiences. 👍