Question: Over the past five years, I've had a few big slot machine wins worth $500 or more. Each one of those wins hit on one of the first dozen or so spins of a session. I've never had a big payout when playing for long stretches of time, only during the first couple of minutes after sitting down.
So, is playing on one machine for long periods really just throwing away time and money? And how does the machine actually know when one player stops and another starts? Can I fool it by changing player cards or depositing more money?
Answer: You are right that most people experience big wins early on in a playing session; but that is simply because of your perception of a session and has nothing to do with how the slot machine actually works.
Firstly, all slot machine spins are determined by a Random Number Generator (RNG). The RNG has one single purpose – to generate random numbers. Nothing else matters; the presence of a loyalty card, the type of deposit (cash or tickets), the length of a session, even the results of the previous spin, these are all irrelevant to the results of the RNG.
Therefore, it does not matter how long or short a slot machine session is, you always have an equal chance to hit a big win. The chance of hitting a jackpot on the 5th spin of a session is the exact same as on the 50th spin, or the 500th spin for that matter. The reason that it seems like you always hit big payouts early on in your sessions, however, is that you probably have a lot more short sessions than long ones.
Nearly every slot session lasts at least 10 spins, but very few players do well enough to still be sitting at the same machine a few hundred spins later. The very nature of slot machines means that they go through cold spells which can eat up credits incredibly quickly. And most players won't keep feeding a seemingly 'losing' machine an endless supply of money, they just find a different game or pack up and head for the bar. So while every slot session has a first spin, very few sessions have a 1000th spin.
So, it's true that more wins come in the first dozen spins, but only because there are a lot more first dozen spins. The odds themselves stay exactly the same.
Question: What is better as far as player's club comps and perks: For two people to play slots using their own cards, or for them to both play on the same card and build points faster?
Answer: It's impossible to say one way or the other; it depends on how the particular player's club you are talking about works.
For accounts with multiple levels where rewards increase significantly as you move into higher tiers, it can be advantageous to have two people play together to move up as quickly as possible. This is especially true when you can redeem points for free play and being in the higher tier means you earn more points without having to actually bet any more than normal.
On the other hand, casinos often use player's club rewards to entice players to return to the casino. Since even small-time players cant be offered free meals, show tickets, or free play through direct mail or email, both people can get these bonuses and added together, they might be worth much more than the points earned from working together on one card. Without more specifics, there is no way to tell.