Closing corotuine question

If I were to close a coroutine, would it come back for any reason, even if I didn’t call it back alive?

If a game were to be lagging because of a coroutine, would closing the coroutine kill the lag?

The reason I ask this is because I know sometimes when a player dies, the scripts reset, and I wouldn’t want unnecessary coroutines running.

When a script is destroyed its execution is stopped and any memory consumed by it is reclaimed by the client/server.