Why can't people stop playing Fortnite?

How the latest video game craze mixes up the fundamentals of game design and human psychology to make itself compelling

Almost every video game is designed to make you want to play it. Fortnite, though, is especially good at keeping people coming back, week after week, match after match. This "stickiness", as game designers call it, is not down to some revolutionary new game design factor. Instead, Fornite has improved and repackaged ideas, creating an effective evolutionary step rather than a leap.

While improving shooting skills and chasing a Victory Royale is satisfying, what keeps Fortnite players engaged second-to-second is loot, the items and weapons that can be found all around the map. The random nature of these item-drops, in quality and location, leads to what is known in psychology as a variable-ratio schedule. A weapon or item that could bestow a significant advantage might always be right around the corner. The hope of finding something desirable paired with occasional reward is exciting to humans: you've probably experienced this from shopping sales, or fishing.