inefficient

Inefficient is an adjective used to describe something that uses more resources than necessary to achieve a given result, or that produces less output per unit of input than is possible. The opposite term is efficient, and the related noun is inefficiency.

In economics and engineering, inefficiency refers to suboptimal use of resources or a production process that leaves unused potential. In energy and manufacturing, an inefficient device or process wastes energy, time, or materials and may generate undesirable byproducts such as excess heat. In computing or business workflows, inefficiency can arise from redundant steps, poor design, or suboptimal algorithms.

Common causes include outdated technology, bottlenecks, poor planning, misaligned incentives, and variability in demand. Some inefficiencies persist for reasons of reliability or flexibility, such as buffering or redundant procedures, but they still reduce overall performance.

Measuring inefficiency involves comparing actual performance with a benchmark or best-practice standard, using metrics such as energy use per unit, cost per unit, cycle time, or throughput. Improvement strategies include process simplification, automation, better design, training, and investment in more capable technology.

The term dates from English usage related to efficiency; the prefix in- indicates negation. It is applied across disciplines to describe suboptimal or wasteful performance, whether in machines, systems, policies, or operations.