The 2014 was one of the deepest in terms of the talent available on Days 2 and 3. That also means a very talented crop of undrafted free agents, as players slip through the cracks.
With undrafted free agents, the goal is always to supplement the bottom of the roster with quality depth and competition. A low hit rate should be expected. Of the immediate undrafted free-agent signings of 2013, only one made a final 53-man roster, and only one made the practice squad. Three of those players are currently on the Minnesota Vikings' roster.
A higher number could make an impact in 2014, though. Mike Zimmer and his staff have preached the importance of competition. If one of these undrafted free agents has the quality of play to merit a roster spot, he will get it. Minnesota brought in a talented group.