Pi can be as it's (thought to be) normal (all digits appear with uniform frequency), but like anything, it's how you use it. Imagine you selected a digit from p

Pi can be as it's (thought to be) normal (all digits appear with uniform frequency), but like anything, it's how you use it. Imagine you selected a digit from pie and used it to decide rock, paper, or scissors (3 options, so let's take a digit and mod 3) 0: 0 Rock 1: 1 Paper 2: 2 Scissors 3: 0 Rock 4: 1 Paper 5: 2 Scissors 6: 0 Rock 7: 1 Paper 8: 2 Scissors 9: 0 Rock Now, let's check the frequency of each option: 0/Rock: 4 1/Paper: 3 2/Scissors: 3 Your RNG is biased towards 0 here. The same thing happens, and is very common, when people just take the system random number generator and mod it by the number of values they want. They always end up biasing the bottom section of their distribution. The common way of dealing with this is to "ignore" any number that would make the set biased. Here you would ignore 9 and you have an even distribution. So, you're playing 7 rounds of RPS and you go 3/R 1/P 4/P 1/P 5/S 9! SKIP! 2/S 6/R