The trigger condition for winning a bingo jackpot (when it isn’t the regular winning condition) is something that doesn’t happen every time. It is nearly always a condition whereby you have to get to the winning pattern, or coverall (full house in the case of 90 ball games) within a certain number of calls.
The required number of calls is usually a maximum, thus in say a 90 ball game, where the main final prize is for the full house, the jackpot condition might be to get this full house in ’40 calls or fewer’. In that (theoretical) case if you get the full house with the 41st call number, then you just get the regular prize.
With 75 ball bingo you can have special patterns as well as the coverall, but the same principle usually applies whereby you have to get the pattern (or coverall) within a certain number of calls or fewer. So, as we can see there is a lot of variation in bingo jackpot games, the types, the trigger conditions, the amount of the prize and whether it varies (gets bigger as it isn’t won) and so on.
This is all without considering special themed games, with aspects and ‘games within games’ over and above the regular kind of traditional bingo!