Cold knowledge, the higher the kill count, the more engaged the players are.

Recently, while reviewing the design of slot machines, I discovered a very realistic yet cruel pattern: some players, the more they lose, the less likely they are to leave, and the more they are defeated, the more agitated they become.

In the eyes of the players, the slot machine is a mysterious and tough "opponent". When they lose, they don't think there is a problem with the machine, but blame themselves for "bad luck today", and thus keep increasing their bets, reinvesting, hoping to break even.

Especially those emotional, gambler-type players—the more fiercely they are defeated, the more it triggers their obsession with "I must win it back", as if they were enchanted by the machine, becoming more and more agitated.

People around them also shout: "It's about to pay out, it's about to pay out", as a group indulges in self-delight.

But note: the kill rate is not the bigger the better. If it's too harsh, not giving even a glimmer of hope, even submissive players can't stand it, and new players will turn away immediately.

Those who truly understand design know that the killing must be rhythmic:

Occasionally give a little sweetener (small jackpot), making people feel "there's a chance";

Control the kill rate in the middle phase to recoup profits;

At critical moments, allow a big payout to create the illusion "this machine is about to take off";

Most importantly—make players feel they were just a little short of winning, which brings on the addiction.

In summary: the kill rate must be harsh, but not heartless; it should make people hurt and chase, but not despair.

This is the highest realm of grasping human nature.