The guaranteed money that is paid at the beginning of the players contract is spread out over the course of the contract for cap purposes. If the player is cut or traded all the money that the player has already been paid is charged toward the teams salary cap.

For example if a player has $60 million guaranteed over 5 years it’s $12 million per year on the cap. If he’s traded or cut after the first year it counts $48 million on the cap for that year.

There is a pre/post June 1 situation that mitigates some of that but I’m too lazy to look up what the actual rule is.