Snowballing effect is descriptive of an entity or situation where requirements defects that appear small and relatively insignificant during Analysis phase grow exponentially at a swift pace, engulfing Design, Development, Testing and Implementation in their path. Similar to a snowball, poor quality requirements create more defects as they descend in the lifecycle phases. The snowball accumulates not only size, but speed, and so are poor quality requirements.

Poor quality requirements produce poor quality design, poor quality products and services, poor quality testing, and poor implementations. Therefore, requirements related repairs are not just limited to requirements, but apply to many artifacts downstream depending on when in the lifecycle the requirements defects are found and fixed.