Excellent exposé about all of the ways slot machines are rigged to screw you.
.Machines that Pick Your Pocket – AND MAKE YOU LIKE IT! —Inside Story of the Slot Machine Racket
by WALTER A. RASCHICK
No matter how clever you are, you can’t beat the slot machine racket. If you play the game, you’ll have to reconcile yourself to seeing your nickels flowing away in a steady stream, paying tribute to the engineering brains which have designed these mechanical pick-pockets so efficiently that they can’t fail to keep half or more of the coins fed into them, giving the player nothing in return except the thrill of seeing his money vanish.
“GOSH!” you’ve probably said more than once, as the symbols halted, hesitated, and then swung tantalizingly away from the center row, “I almost got the bells that time. Watch this one” —and out of your pocket and into the slot machine goes another hard-earned nickel.