Variance
The natural swing in results caused by luck in the short term. Even a winning player has losing months; variance is measured in buy-ins or big blinds per hundred hands and dictates how big a bankroll you need.
Frequently asked questions
What is variance in poker?
The statistical spread of outcomes around your long-run expectation. It is the reason a winning player can lose for months and a losing player can have the best year of their life.
How long until variance evens out?
Longer than almost anyone expects. Cash results need tens or hundreds of thousands of hands before a win rate is meaningful, and tournament players may need years of volume — because almost all the profit comes from a handful of deep runs.
How do players cope with it?
By separating decisions from results: reviewing whether a hand was played well rather than whether it won, and holding a bankroll large enough that a normal bad run is survivable. Formats differ too — tournament variance dwarfs cash-game variance, and high rollers dwarf both.