Depends on luck I think, if luck always accompanies in every time we gamble, in a long term too will not loss and will continue to generate profits. If we often experience defeat i think to play long term will not generate profits and will be very harmful. Luck and skills are very influential on the profits in gambling not about time only on it.
But its not possible to keep on making profits in each and every game and most of the times only house will win so I don't that either in short term or in long term gambling can ever be profitable and it will only take away your money.