The thing is, not only were The Beatles incredibly talented (of course), but they did NOT surround themselves with dummies, but the very best in the business. And not only were they the best in the business, but they had great chemistry with the band, as well. So they worked well together and were able to make magic that none of them would have been able to make on their own. And by on their own, I am including the 4 members of the band as a single entity, here.
For those of you who have not read it, I am giving the strongest possible recommendation that I can to THIS BOOK:
The Complete Beatles Recording Sessions: The Official Story of the Abbey Road Years 1962-1970 by Mark LewishonI read it, myself, a couple of years ago and, what struck me most, more than anything else, was... just how damn HARD those boys worked. And not only how hard they worked, but how hard everybody around them worked. It was a pretty big team that made those classic albums, and I do mean TEAM.
Seriously. It is essential reading.