Psychological Law

Cobra Effect

A well-intentioned solution makes the original problem worse.

Origin & History

The term was coined by economist Horst Siebert in his 2001 book Der Kobra-Effekt. The name comes from an incident during British colonial rule in India: to reduce dangerous cobra populations, the government offered cash rewards for dead cobras. Initially effective, the policy backfired when citizens began breeding cobras at home to collect the reward. When the government cancelled the program, the breeders released thousands of now-worthless snakes — leaving the cobra population larger than before the policy began.

Real-World Examples

Colonial India Cobras

The British colonial government's cobra bounty program ended with more cobras than before — because the incentive created a cobra-farming industry that flooded the population when the incentive was removed.

Traffic Rationing

A city introduced alternating odd/even license plate restrictions to reduce traffic. Within a year, average households owned two cars — one odd-plated, one even. Congestion doubled.

Hospital Discharge Metrics

Hospitals rewarded for fast patient discharge improved their discharge speed — and also their readmission rates, as patients were released before recovery. Optimizing the metric made the underlying health outcome worse.

Why It Matters

The Cobra Effect is a special case of Goodhart's Law: when an incentive is created to address a behavior, the behavior adapts to optimize for the incentive rather than the underlying goal. Any incentive system that can be gamed will be gamed. The pre-mortem question for any policy or incentive: 'If people optimize entirely for this metric and ignore everything else, what happens?' If the answer is bad, the design is vulnerable to a Cobra Effect.

Related Laws

Can You Spot Cobra Effect in the Wild?

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Frequently Asked Questions

What is the Cobra Effect?

When a well-intentioned incentive or intervention produces perverse outcomes that make the original problem worse — named after the British colonial cobra bounty program in India.

What is the difference between Cobra Effect and Goodhart's Law?

They are closely related. Goodhart's Law describes the general problem of metrics becoming targets; the Cobra Effect describes the specific outcome where the 'solution' actively worsens the original problem.

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