rework

Rework refers to the set of activities required to correct or revise a product, service, or process after it has begun its next stage of production or development, in order to meet defined requirements or customer expectations. It covers outputs that fail to conform to specifications, changes in design, or defects found during inspections, testing, or user validation. Rework is encountered across many domains, including manufacturing, software development, construction, and services.

In manufacturing, rework applies to nonconforming items that must be repaired, modified, or reassembled to meet quality standards. It increases cycle time, consumes labor and materials, and can disrupt production lines. In software and IT, rework typically means altering code, documentation, or configurations after testing or review; it often follows bugs, scope changes, or integration issues and may motivate refactoring.

Causes and impacts: common drivers include design errors, specification changes, miscommunication, measurement mistakes, or late defect discovery. Rework raises costs, delays deliveries, and reduces throughput; excessive rework can erode competitiveness.

Mitigation: implement robust requirements engineering, design reviews, process standardization, and early testing; apply quality control, mistake-proofing, modular design, and continuous improvement to limit rework. Track metrics such as rework rate and cost of quality to identify hotspots.

In popular culture, Rework is a book (2010) by Jason Fried and David Heinemeier Hansson that argues for lean business practices and less vanity work; the term is also used in software to describe refactoring or rewriting code when necessary.