Emphasis on veterans
As mentioned earlier, the Colts seem to be harping on adding a veteran presence to the defensive side of the ball. Chris Ballard mentioned earlier in the offseason that allowing some of the veterans to walk in free agency had a negative impact because of what they bring to the locker room.
In addition to Carrie joining the secondary, the Colts also signed veteran cornerback Xavier Rhodes, who has extensive work as a starter in the league. Defensive tackles DeForest Buckner and Sheldon Day also bring a veteran presence having been key cogs in the defensive line for the San Francisco 49ers over the last few seasons.
Carrie certainly has experience playing in the league, which in turn should help the younger players develop.