Managers often want to know the percentage of work done. Let’s say the feedback would be “we’re 50% done”.
When a project manager responsible for a waterfall project gives this feedback, it’s not really clear what he means. It can mean that the project plan is halfway through, that half of the budget is spent, or half of the work is done. Even in the case of the latter, the customer still didn’t receive any deliverables yet.
The first and the last value is delivered at the moment of release.
When a scrum master gives this feedback, it means that half of the user stories are delivered. Because the highest-value user stories are typically implemented first, this message automatically also means that at least 50% of the value has been delivered.
Assuming that also the highest-risk stories are amongst the first ones to be implemented, the same message also means that at least 50% of the risk has been reduced.
Whatever happens to the project, the delivered value can not be taken axay. Even if the project fails, half of the value will remain delivered to the customer.