unintended consequence
Surprise ripple effect
An unintended consequence is a result that wasn't anticipated or planned for when an action was taken.
The term usually appears in discussions of policy, technology, or large-scale decisions where secondary effects emerge that no one foresaw: The law had the unintended consequence of driving up prices.
Unintended consequences may be beneficial, harmful, or neutral—the phrase itself carries no judgment, though it often introduces problems.
- side effectUnintended secondary outcome
- backfireYield unintended consequences
- accidentUnintended harmful event
- unforeseen circumstancesUnplanned events affecting outcomes
- best laid plansThorough preparations that fail
complex systems · serendipity · ripple effect · knock-on effect · foreseeability · byproduct · collateral damage · emergent behavior · oversight · domino effect · fortuity · spillover · fallout · miscalculation · playing with fire · opening Pandora's box · ramification · feedback loops
- comic mishapsmistaken identity, misunderstanding, mix-up, miscommunication, blunder
- accidentsaccident, car accident, bike accident, mishap, traffic accident
- what-ifswhat if, hypothetical, thought experiment, speculation, conjecture
- ironic twiststwist of fate, poetic justice, dramatic irony, situational irony, tragic irony
unintended, consequence, intended, intend, intends, intending, intent, intention, intentions