Drafting a player at a position That's not an immediate need makes sense, and it clearly paid off.
Signing an aging expensive FA at a position of strength doesn't
To be fair the average success of each Team in a Draft class is about 17% using a fair term of three years to determine;Pro Blow caliber, Starter, Valuable Back up/ST or out of the League versus injury, disappointing misjudge of talent, wrong Team fit as in "square peg in round hole". That works on one of two guys per Team. Ironically the worst Teams keep the most picks as they have the most holes to fill.
Now the percentage of success in said Draft Class is proportional to the round selected, as in the higher picks have the best success rate, but from Round 1-7 it averages about 17% league wide. If you are a first round pick, chances are in three years you will be the remaining one or two of that Draft Class on your Team.
Do not include "roster fillers" in your dynamic. The Pats had many rookies make the Team to fill roster spots and might stay a year or two. Some will rise from the ashes , others not so much.Think Tavon Wilson, Chad Jackson, Dowling or Brandon Tate. Now Tate became serviceable on the Bengals but that does not count on the Pats 17%
The Pats do better than most 2012=3, 2013=3, 2014=4 with a large sampling of 9 picks plus will Easley's health stand up or will Jimmy G get traded? . Some Teams do not have a single pick remaining after year three so it is an average.
Making the Team year one does not qualify for full Draft Class success. Chances are someone better gets Drafted/FA as you compete for your job.
The success rate for a selected Free Agent is much higher. It is attributed to prior on the field success and NFL game film versus college. I don't have that percentage but if you look at a sampling of the last three years it hovers at about 55-60%. So yes, FA will be a better position choice and less of a gamble but injury and age are a factor.
i.e. If we are looking for a WR to hit in 2016 we are more apt to have a proven WR work out in year one than a Rookie. Unless you Draft high enough for a Cooper or Julio Jones.
What I am saying is you can't always gamble you can fill a hole with a pick. Hence the term "best player available". But you can target a player or position of need in FA.
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