Every agency has the scope creep war story. The project that started as a two-month engagement and ran for eight. The feature that was "just a small addition" and consumed three sprints. After a decade of client work, we think the diagnosis most people reach for — unclear requirements, scope not locked down — is only half right.
The spec everyone agreed to but read differently
The most common root cause we see is a document that looks complete but contains ambiguity everyone tacitly resolved in their own direction. "User can filter results" means a dropdown to the developer, an Elasticsearch-powered faceted search to the client, and a natural-language query interface to the VP who approved the budget.
The solution is not a longer spec — it is a demonstrated prototype. Get working software in front of stakeholders within the first two weeks. The disagreements surface immediately, before they have accrued interest in the form of built code.
How we handle it now
Every engagement at Atero starts with a two-week discovery sprint that produces a clickable prototype, not a requirements document. We time-box every subsequent phase. Change requests are logged, estimated, and acknowledged — not refused, but surfaced with their cost made explicit.
This does not prevent scope creep entirely. But it changes the conversation from "that was always in scope" to "here is what it costs to add that" — which is a conversation both sides can resolve professionally.