A Quick Note on the Browns' Carryover Cap Space

We have discussed the fact that the Cleveland Browns were projected to carry over $20.73 million in cap space. Today, the NFLPA officially confirmed that amount with this awesome infographic that illustrates how much each team in the NFL carried over from the 2015 league year to the 2016 league year:

The official amount for the Browns is $20,734,144. At the bottom of the infographic, you'll see the asterisk noting that the Broncos, Rams, and Saints opted not to carry all of their space over. If my estimates are right, the Rams didn't carry over about $1.2 million; the Broncos $200,000; and the Saints about $42,000. What is the explanation for teams not carrying over the full amount?

The best explanation we could find is here, which describes why the Rams have made a habit of doing this. For example:

In 2014, the Rams finished with nearly $700,000 of salary cap room and $2 million of incentives that had not counted. Therefore, they did not rollover the $700,000. Instead, they used the $700,000 to reduce their incentive netting. The end result is exact same cap amount as if we had rolled remaining room over.

In a case like that, you could see why it might also help the team if they needed to cut a player with a base salary guarantee in a future year -- they might have been able to do so prior to issuing incentives.