Variable Rewards
Unpredictable or random rewards are more addictive than a predictable schedule.
Casinos know that slot machines are more addictive if they pay out a random reward at unpredictable times. If people always won back 80% of their money on each pull of the lever, it wouldn't be an exciting game and wouldn't be addictive. It's the unpredictable and random nature of the rewards that keeps people playing with the hope for that rare big jackpot.
A constant or predictable schedule of rewards is not very exciting. This is why games often randomize the rewards that you receive for finishing a level or defeating an enemy. By making the rewards like a slot machine, they are trying to make the game more additive. They may also be trying to extend gameplay by making you grind longer to get what you want. If you need a certain item, but it only appears as a reward 5% of the time, people will keep playing over and over with the hope of getting that rare item. If the game has limited energy and forces you to wait to play then people may end up paying money to skip the wait.
A constant or predictable schedule of rewards is not very exciting. This is why games often randomize the rewards that you receive for finishing a level or defeating an enemy. By making the rewards like a slot machine, they are trying to make the game more additive. They may also be trying to extend gameplay by making you grind longer to get what you want. If you need a certain item, but it only appears as a reward 5% of the time, people will keep playing over and over with the hope of getting that rare item. If the game has limited energy and forces you to wait to play then people may end up paying money to skip the wait.
Citations and Sources • Why are Video Games Addictive?
• Behavioral Game Design
• 5 Game Mechanics that Make Games Addicting
• Wikipedia :: Reinforcement
• Behavioral Game Design
• 5 Game Mechanics that Make Games Addicting
• Wikipedia :: Reinforcement
Examples
Pokémon Sleep"Rewards per leveling"
Star Trek Timelines - Strategy RPG & Space Battles"There is effectively a loot box system, where you get a random chance of gaining a character. You are guaranteed a base level character, but the higher level characters are much less likely to drop."
Soundmap: The Music Game"Level ups and quests i guess???"
GraalOnline Zone+"The “daily rewards”, or missions."
Honkai: Star Rail"Rewards are given out in variable amounts for completing quests; the amount depends on quest length"
SOULS"Especially rifts and artifacts are very rng reward heavy"
AFK Journey"The time-limited bundles that only appear when you complete a certain task are not fixed at the same value. Some people will get better value than others. This is extremely unfair and disadvantageous to spenders."
Geometry Dash Lite"Playing levels can give you keys that open chest that give randomized loot"
Bloons TD 6"Finishing round 100 gives random insta-monkeys, collection events give random insta-monkeys."
Squad Busters"Random chest loot and rewards through multiple tracks."