The Cost of Using Flags in a Team

Do you leave them there so you can always stolglo if needed? Or at one point the feature is just acor are we to say, no, flag stay there forever. Is there like a prime line? You say, we make this ticket and it has a dead line in always three months? Or does this depend on the type of feature? I'm not sure that i've seen a team woulh like a hard and fast rule on that dead line. It's more about what is kind of the total load of flags your team can be maintaining at once, than the lifetime of a particular flag.