Lesson 03 · 3 min · 5 things to do
Randomness that feels fair
Explain why true randomness feels broken to players.
An attack has a 30% chance to hit. A player misses five times in a row and calls the game broken. Are they right?
- Yes.0.7 to the fifth power is 0.17. With thousands of players attacking constantly, streaks like that happen every minute somewhere, and each one feels personal.
- Not quite.It is exactly what a fair 30% produces. Runs are a property of independent chances, not a sign of a bug.
- Not quite.It is directly calculable, and one in six is common enough to expect it constantly.
True randomness produces streaks. Players experience a streak as evidence of a lie, which is why many games do not use true randomness at all.
Slide between true randomness and a system designed to feel fair.
True randomRising chanceGuaranteed after NChance of missing 5 in a row17%Chance players call it broken90%True randomEvery attempt an independent 30%. Long streaks of misses are routine.
Chance of missing 5 in a row1%Chance players call it broken10%Rising chanceEach miss raises the next attempt's chance. The average stays near 30% and the streaks vanish.
Chance of missing 5 in a row0%Chance players call it broken5%Guaranteed after NA hit is promised by the fourth attempt. Predictable, and now players plan around it.
The middle system is less random and feels more fair. What has it changed?
- Yes.It is a standard technique in competitive games. The honest description is that the game is less random than it says, in a direction players prefer.
- Not quite.The long-run hit rate is about the same. Only the distribution of streaks changed.
- Not quite.True randomness was already fair in the mathematical sense. What changed is how it feels — which is a different property, and the one the designer chose.
Move the control to see what changes.
Which of these does a player perceive as "random but fair"?
Losing a coin flip after winning three.
Missing six 80% shots in a row.
A rare drop appearing after many attempts.
The enemy hitting every low-percentage attack.
A visible chance shown before you commit.
Yes.People judge randomness by whether the run looks like their idea of random, and their idea has too few streaks in it. A designer either fights that or accommodates it — and most accommodate.An attack hits 80% of the time. What is the chance of missing three in a row, as a percentage?
%Yes.0.2 cubed. Under one percent per player — and across a million players that is 8,000 people every session, each convinced the game cheated.A game shows you a 95% chance and you fail. What have you learned about the game?
- Yes.The memorable failure is the one at high odds, which is why 95% shots are remembered and 60% ones are not. The percentage is a statement about frequency, not a promise about your turn.
- Not quite.Possible in principle, and one failure is exactly what a truthful 95% produces one time in twenty.
- Not quite.Some games do adjust them. One outcome cannot tell you that.
Lesson complete
True randomness produces streaks, and streaks feel like a lie.
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