Dice would be the fastest one to make some bucks. You win or lose. This will be done in a few seconds compared with slots that it takes a very long time waiting for the multiplier to come. Actually this is depend on our luck. If people are suffering the lose and just take them were not lucky enough in gambling. If you are lucky enough and you can get profit from doing various game. your luck is the main concern.
Why Dice is fastest? You can go all-in in ANY game, like roulette, poker and so on (I've said it before here). So I would sum, that ANY gambling game CAN be fast profitable (the same as fast lose). This depends not from a game you choose, rather from your gambling style