Originally Posted by scott1212

It's truly random. What you're noticing is simply noticeable -- which makes it memorable -- you don't notice all the times it *doesn't* happen that way.

People are constantly searching for patterns in what are essentially random acts, and slot machines are no different. That's how our brains are wired. We find patterns in the noise, but the patterns are just as random as the things that don't look like patterns. In any random set of data, there will be things that look like remarkable patterns -- "amazing coincidences." But the reality is that it's random and our brain just pulls out the patterns to help us make sense of it.

And slot machines are no different. Slot machine designers take advantage of this fact of human psychology. The design of all of the slot symbols is no accident. They're designed to make us notice patterns -- and to keep thinking how "close" something was to a match based on the similarity of the patterns. In reality, the symbols might as well be blank, because there's no significance to them. Getting four out of five 7's in a row is mathematically the same as getting one out of five 7's, but we get excited in the first case because we think we were "close," or maybe getting "closer." Everything about the slot machine -- the visuals and the sounds -- reinforces this, and it's no accident.

The random number generators are in no way affected by the presence of absence of Players Club cards. In fact, slot machines use a completely different microprocessor and hardware to manage the Players Club functionality. That hardware only sees "credits in," and doesn't even know the result of a spin.

But casinos don't mind if people think there are "hot" machines or if people have rituals they perform for luck, etc. -- because the cold, hard facts of statistics aren't that exciting and if people only thought sensibly about the statistics, few people would gamble. So casinos are happy to oblige; one example of this is how they have the number boards that show what numbers and colors have hit on roulette wheel the past dozen or so spins. Those numbers are completely, statistically meaningless -- roulette spins are memoryless, meaning the current spin is not affected in any way by the result of prior spins. If red hits 20 times in a row, it is just as likely to hit on the 21st spin as black. But people like to find patterns, and instinctively think that the numbers are compelled to balance out, so the casino is happy to put the number history up if that makes people more emotionally vested in the gambling.