The continual enhancement of the requirements of a project as the system is being constructed. Also called "feature creep," scope creep occurs frequently in information systems development and is often responsible for projects going way over budget if the changes occur in the coding and testing stages rather than in the early design stages.
It seems to be the nature of humans that we cannot figure everything out at the start, and today's systems can be exceedingly complex. Refinements often come during the latter stages, because users, analysts and programmers have gained more experience after new functions are staged into operation. "Rome wasn't built in a day!" See
prototyping and
estimating a programming job.