... Pete, being the highly logical, calculating person he is, rejects all of that as superstitious nonsense. He instead applies the scientific approach. Over the years, he's collected somewhere around a thousand twenty-sided dice. Every so often, he gathers them all together. He sits down at a table and carefully and individually rolls each of the thousand dice, once. Of course, roughly a twentieth of them will roll a one. He takes those fifty-odd dice and rolls them a second time. After about an hour of concentrated dice rolling, he'll end up with around two or three dice that have rolled two ones in a row. He takes those primed dice and places them in special custom-made padded containers where they can't roll around, and carries them to all the games he plays.

Then, when in the most dire circumstances, where a roll of one would be absolutely disastrous, he pulls out the prepared dice. He now has in his hand a die that has rolled two ones in a row. Pete knows the odds of a d20 rolling three ones in a row is a puny one in 8,000. He has effectively pre-rolled the ones out of the die, and can make his crucial roll with confidence. Furthermore, being scientific about it means he knows that it doesn't matter who rolls the die for the third time, so he has no qualms about sharing his primed dice with other players, if that's what it takes to avoid disaster."

Genius. Sheer genius.

Except that to get ready for that roll, he has already made thousands of dice rolls. He has been pulling out those dice that rolled two 1's, which means he has not rolled 3 1's in a row yet. It may be a 1:8000 chance, but if he's just rolled 7,999 dice without getting that result.... what's bound to happen?

Add to that the fact that no single dice is truly random. A single extra µl of plastic on one side could weight it

* slightly* towards a certain result. So by gathering the dice that roll 1's more often, he is in fact biasing his rolls TOWARDS 1.

I'll take my animistic-inspired tactics of intimidation and destruction of dice that roll poorly. "Okay frosted white d20. You've rolled 4 1's this session, and nothing above a 4. You need to get your shit together, or I'm going to throw you out onto the highway in front of the shop. Let's give you one more try..."

... It may be completely stupid and illogical, but at least it's a neutral bias at worst, and a selective destruction of poorly weighted dice at best.

Also it confuses the townies, who find a decent number of d20s in the drains nearby, ever since other people started "301"ing their sucky dice.