In general, kids from my high school who have done well going pre-med have been those where their stats are in the Top 25% of students attending.
I suspect this is because it shows they have the foundation to be competitive with the other top students. Work ethic still has to be there (because academic smarts isn’t everything), but when one has less of a foundation than other students in basic classes, it makes them feel inferior. That leads to stress of another kind - difficult to overcome, even if their capability is the same if they had had the same foundation.
I see this often enough that it’s become something I highly recommend when talking with students who think they want to go to med school. The actual school doesn’t really matter. Pick based upon fit and finances.