Scope creep is the gradual expansion of a project beyond its originally agreed deliverables — extra revision rounds, additional assets, or new requests added incrementally without formally adjusting the timeline or cost.
It usually happens gradually and with good intentions on both sides — "just one more small tweak" repeated enough times adds up to meaningfully more work than was originally scoped or priced.
A clearly defined statement of work with specific deliverables and revision limits is the most effective prevention — when a genuinely new request comes up mid-project, it can be addressed as a scoped addition rather than folded silently into the existing agreement.