As much as we all like to pretend, progress isn’t linear in the NFL. Not all rookies make a big jump from their rookie year to their sophomore season. Sometimes, development is arrested by things outside of the players’ control, like an injury. Taylor Decker can tell you all about that.
Other times, we just assume a player will get better after spending a year to get more comfortable in the league. That makes logical sense, but it just doesn’t always turn out that way. A guy like cornerback Alex Carter was due for a breakout season in his second and third years, but that never ended up happening.