I would imagine that repairing it would mean it'll be out of commission for a few hours up to a few days, for example by waiting until the repair techs arrive or whatnot, interrupting regular operations. Depending on how the costs are counted, even just a few hours can quickly catch up if you add all the personal costs of the sailors on the ship etc.

It's the same with things like outages, an outage lasting a day may "cost" $1 million, but what's actually meant is that you missed $1 million in profits for the day, not that you had to pay $1 million. If operating a carrier costs $400k/day then you could say then fixing something for a day "costs" $400k, but that's kind of a simplistic way of putting it.