overruns

Overruns refer to outcomes that exceed planned limits and are used across multiple domains, including project management, construction, aviation, and military operations. They describe situations where actual results surpass what was anticipated in terms of time, cost, capacity, or space.

In project management, a cost overrun occurs when actual costs exceed the approved budget, and a schedule overrun (or delay) occurs when completion stretches beyond the planned timeline. Overruns are commonly expressed as percentages, calculated as (actual minus planned) divided by planned.

Common causes include optimistic estimates, scope creep or changes in requirements, unforeseen technical challenges, regulatory or permitting delays, inflation and currency movements, resource shortages, and integration issues. Risk events can accumulate, leading to compound overruns.

Impacts of overruns can be significant, including higher funding needs, delayed benefits, reduced return on investment, and reputational risk for organizations. Effective management typically relies on upfront risk assessment, contingency reserves, strict change control, and monitoring approaches such as earned value management.

Domain-specific notes: In construction and infrastructure, overruns are a frequent concern for large projects. In software development, overruns are often linked to scope creep or the emergence of technical debt, with agile practices aimed at early delivery and incremental scope control. In military terminology, an overrun denotes a rapid enemy penetration into territory. In aviation, a runway overrun occurs when an aircraft continues beyond the end of a runway after landing; safety measures focus on braking performance and incident investigation.

Variants of overruns include time overruns, cost overruns, and capacity or workload overruns, as well as cases where multiple dimensions exceed plans simultaneously.