An accepted proposal is not the end of internal coordination. The delivery team needs to understand the outcome the customer wants, the work the supplier has committed to provide and the conditions required to perform it. Those elements are connected, but they are not interchangeable.
A handover should make negotiated exceptions visible. An extra session, a scheduling adjustment or a specific adaptation may require resources that the standard plan does not include. The exception itself may be reasonable. The risk is losing its context, ownership or operational cost between the sales conversation and the start of delivery.
The team also needs to distinguish an option discussed from a commitment confirmed. Uncertainty should trigger clarification before work creates further expectations. A concise record of final commitments is often more useful than asking colleagues to reconstruct an entire message history.
Operational staff must have a way to question feasibility, dependencies and capacity. That review should help the organisation deliver, rather than become a contest between departments. It should also establish who decides when a change affects scope, timing or resources.
Customers should not have to rely on the right employee remembering the right conversation. A deliberate handover makes the promise understandable to the people responsible for keeping it.