Cost overrun

Cost overrun happens when a project costs more money than was originally budgeted for. For example, if you made a plan for a company to build something and you said it would cost $100, but it actually cost $120, then the $20 cost is the cost overrun. Essentially, cost overrun is when something is more expensive than expected.

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Admissible heuristic, Benefit shortfall, Downside risk, Efficient contract theory, Escalation of commitment, Hiding hand principle, Megaproject, Optimism bias, Planning fallacy, Reference class forecasting, Scope creep