The analytically defined value here lies in past data showing that developing a quarterback in a system (and with a playbook) optimized for his best attributes leads to greater NFL success as measured by wins (SEE: Jimmy Garoppolo). Broadly speaking, the data works out like this: In critical areas that are correlated with greater win percentages -- limiting turnovers, producing on third down and in the red zone -- QBs who get to add complexity to the playbook as their experience level increases win more often, while QBs who have to be more productive immediately do not win as often. Yes, the teams that immediately start rookie quarterbacks are often "worse" overall, but fit and play calling impact execution and results (SEE: Dak Prescott, Jared Goff). It also just makes sense.