The second NFL year can be a break-out party for talented NFL players. For some players, that breakout doesn't happen until their third or fourth years in the league.
It is a widely held belief that NFL players take a quantum leap in performance from their rookie season to their second season. After all, they've been through their first full season, they've been through a full NFL-level offseason strength & conditioning program, they're hopefully a little more mature, and they've had ample time to improve their technique. But that belief usually only applies to higher-round draft picks. For bottom-roster guys, that leap in performance sometimes doesn't happen until their third or fourth year in the league - if at all.