The theory I've been thinking about:
The conventional wisdom is that first round picks need to be instant starters while mid and later round picks carry clipboard and learn. But I wonder if we have that backwards.
Most of the best mid to late rounders (Brady, Montana, Unitas, Starr, Anderson,Tarkenton, etc.) were at least fighting for starting jobs from the beginning. And most of the qbs who bounce around and take time to develop (the Plunkett Model) were first round picks.
Mayfield, Darnold, Goff, Geno Smith in recent years, are good examples.