It's not quite as simple as that. They're programmed to pay out a specific percentage of what they take in over time, but it's over a sliding period of time. If it were just as simple as not paying out regularly, it would be easily exploitable by simply having groups keep track of recent payouts and long runs of small payouts and sending in one of their guys for the machines about to hit. In fact, this has been done in the past when methods were more simplistic. Without (illegally) hacking or otherwise cheating, you can't really do this any more (without using insider knowledge which again would be actually illegal unlike simply observing).
The only real edge you can get on slot machines (legally) is on progressives with high payouts, especially those with multiple machines qualifying for the jackpot, sufficient that the size of the jackpot is higher than the take on the machine itself. Then the group goes in and heavily plays those machines, which can be difficult when they're usually incredibly popular at that point because the advantage is obvious.
Casinos love progressives because they don't have to pay for these jackpots, they're entirely formed from the drop paid by previous players. That's why you see things like bad beat jackpots at poker and huge jackpots on progressive slot machines. Even when they're entirely on the up and up (which I would not assume at an Indian casino) it doesn't actually cost the casino anything when someone hits it. By comparison a crazy Arab who goes on a run at baccarat can put a serious dent in profits.
One way to actually make money at slots, although it isn't always available, is some casinos will have a slots "tournament" from time to time where you pay a fixed fee to play and after the rake, the buyins go into a pool, then by meeting some criteria (like getting the most winnings) you get a cut of the prize pool. Then you play higher variance machines more likely to hit big while the rest of the pool is playing nearly at random.
Slots are otherwise virtually never worth playing because all the obvious methods of exploiting them or predicting their behavior are long closed and the ones remaining are mostly illegal and will get you arrested or worse. I'm sure someone out there is still exploiting some of them and not getting greedy enough to get flagged, but those people don't talk.