World's 10 Most Expensive Mistakes

Chernobyl Nuclear Disaster: Faulty reactor design and operator errors led to meltdown, massive evacuations, and environmental contamination. Cost: Billions.

Deepwater Horizon Oil Spill: BP's rig explosion caused the largest marine oil spill. Economic, environmental damages reached $65 billion.

Space Shuttle Challenger: Faulty O-ring design caused explosion. Lives lost, program delayed. Cost: $5.5 billion.

Titanic Sinking: Infamous ship hit an iceberg due to speed and inadequate lookout. Over 1,500 lives lost. Huge financial loss.

Piper Alpha Oil Rig Explosion: Safety protocol failures caused explosion. 167 lives lost, oil production severely impacted. Cost: $3.4 billion.

Vasa Ship, Sweden: In 1628, the top-heavy warship sank on maiden voyage. Reconstruction efforts centuries later; priceless cultural loss.

Hubble Space Telescope: Flawed mirror affected initial images. Repair mission cost $25 million, not counting shuttle launch expenses.

Ariane 5 Rocket: European Space Agency's rocket exploded due to software error. Lost satellite payloads. Cost: $370 million.

Three Mile Island Accident: Partial reactor meltdown; though contained, it resulted in widespread fear and policy changes. Cost: $1 billion.

Exxon Valdez Oil Spill: Tanker ran aground in Alaska, spilling oil. Environmental and economic damages. Cleanup cost: $2 billion.