The Cardinals would've liked to keep Calais Campbell. And Tony Jefferson (or D.J. Swearinger), and Marcus Cooper too. But the prices got to be a lot larger than the team wanted to pay, and there was a flip side to those players defecting -- and to the way the Cardinals have looked at bringing in free agents themselves over the last few days: Compensatory picks.
Comp picks are the extra selections at the end of each round, starting in the third, that teams get after all the free agent comings and goings are tallied. The NFL keeps the formula for comp picks secret, although a) it's determined by each team's free agents losses and gains, along with the size of those players' new contracts, plus playing time and postseason honors; and b) there are only so many in a draft.
(This was made painfully clear to the Cardinals recently. The Cardinals get an extra fifth-round pick in the 2017 draft next month, and they had qualified for three other extra seventh-round picks -- but the NFL caps the total number of comp picks at 32, and since teams across the league qualified for 39 total, the last seven didn't count. The extra three of the Cards' picks fell in that last seven "dead zone.")
There are other things that dictate the comings-and-goings part of the comp pick equation. Players who are in the league 10 years or more don't matter as much (so the Cards aren't really hurt by the "coming" of Karlos Dansby, who was basically canceled out by the "going" of Alex Okafor to the Saints). This only applies to free agents who had contracts expire (so Antoine Bethea, cut by San Francisco, does not count in the equation.)
A team would max out with four comp picks in any given draft. Right now, it looks like the Cardinals would be in line for four -- four pretty good ones. Those that break this down (the best they can, given the secrecy of the exact formula) estimate the Cardinals gaining potentially two third-round picks in 2018, plus a couple of others. Even if one of the picks isn't a third but a fourth, plus a couple of other later ones in the fifth- or sixth-round to get to the maximum four, it would give the Cardinals a lot of firepower in the 2018 draft. (If it played out like that, it'd be 10 draft picks, because the Cards traded their 2018 seventh-rounder to Kansas City for Cooper).
Nothing is set in stone, but the money is a big driver in comp picks and at this point, you figure the big money in free agency is already gone. If the Cards were going to lose high-profile free agents, they at least figure to get something out of it.
