There is a myth going around that the longer a slot machine has not paid out any winning, the bigger the chance that a payout is coming. Some players watch slot machines and bet on those that are "cold", i.e. have not paid out anything in a while in hopes that the chances of hitting a jackpot is higher than in those that are "hot", i.e. somebody just won something on them.
Please be advised that chances of any spin are irrelevant to the previous spin, the "probability clock" is reset after every turn.