A shutdown runs over a weekend. The supervisor asks two technicians to come in on Sunday and tells them they will get a day off in return.
Nobody writes it down. Eight months later one of them resigns and claims two days. HR has no record, the supervisor has moved on, and the company is choosing between paying a claim it cannot verify and refusing one that is probably genuine.
The verbal promise is the whole problem
Comp-off is unusual among leave types in being created at the moment of an operational decision, by a person who is not in HR, usually under pressure.
That makes it the entitlement most likely to exist only in somebody's memory — and memory is not symmetric. The employee remembers two days; the company remembers nothing.
Credit it, date it, expire it
Three things make comp-off work.
Credit it as a real balance at the point it is earned, by the supervisor who granted it, in the same system that holds every other balance. If the supervisor can grant it from their phone, they will.
Date each credit, because comp-off is earned on a specific day and its window runs from that day.
Expire it — commonly 30 to 90 days. An unexpiring balance quietly accumulates into a liability nobody planned, and by the time it surfaces it is large. A stated window makes the benefit real to the employee and the exposure bounded for you.
Decide the other question in advance
Does working a weekly off produce comp-off, or overtime at the statutory rate? That depends on the applicable legislation, the employee's category, and your policy — and it is not a choice to be made at the time by whoever is asking.
Decide the rule, write it down, and apply it uniformly. The version where it is decided case by case is the version that produces both inconsistency and a compliance question.
Encashment
Many employers deliberately do not allow comp-off to be encashed, because an encashable comp-off changes the incentive around working rest days in a direction they do not want. That is a legitimate position. What matters is that it is stated rather than assumed.
The check
Ask your supervisors how many comp-offs they have promised this quarter. Then look at how many are recorded. The gap between those two numbers is a liability you are carrying without a figure attached to it.