None of that gets them out of a recheck. New batteries go dead when something draws on them and there is insufficient replenishment. Repeated cycles can "age" a battery, in other words, reduce its ability to recover to what its full charge used to be. A bad cable or defective alternator can be a problem. Incorrectly wired or defective isolator can also lead to a house bank not getting sufficient charger. Dont assume these things are good, test them.