Numerous people at my job (An arcade room) come to me with complaints of games malfunctioning. There is about a 50% chance of it being them not pressing the start button. 25% Think they are being unfairly denied tickets for a jackpot or large sum they did not win. 15% are legitimate problems, or a machine that needs its tickets refilled. Usually the latter. The final 10% is commanded by people who do not know what a quarter looks like, and so think dimes, nickels and pennies can be used in the machines.